All Related Questions of Applied Statistics

Q: Use Excel to generate 100 random integers from (a) 1

Use Excel to generate 100 random integers from (a) 1 through 2, inclusive; (b) 1 through 5, inclusive; and (c) 0 through 99, inclusive. (d) In each case, write the Excel formula. (e) In each case, cal...

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Q: Calculate each compound event probability: a. P(

Calculate each compound event probability: a. P(X < 10), λ = 11.0 b. P(X > 3), λ = 5.2 c. P(X < 2), λ = 3.7

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Q: “Many college graduates will not use very much statistics during their

“Many college graduates will not use very much statistics during their 40-year careers, so why study it?” (a) List several arguments for and against this statement. Which position do you find more con...

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Q: How can you tell when the point has been reached where you

How can you tell when the point has been reached where you should call for an expert statistician? List some costs and some benefits that would govern this decision.

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Q: Which type of data (cross-sectional or time series)

Which type of data (cross-sectional or time series) is each variable? a. Value of Standard & Poor’s 500 stock price index at the close of each trading day last year. b. Closing price of each of the 5...

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Q: Which type of data (cross-sectional or time series)

Which type of data (cross-sectional or time series) is each variable? a. Mexico’s GDP for each of the last 10 quarters. b. Unemployment rates in each of the 31 states in Mexico at the end of last yea...

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Q: Recently, the same five winning numbers (4, 21,

Recently, the same five winning numbers (4, 21, 23, 34, 39) came up both on Monday and on Wednesday in the North Carolina Lottery. “That’s so unlikely that it must be rigged,” said Mary. Which fallacy...

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Q: The probability that a randomly selected student in your class is celebrating

The probability that a randomly selected student in your class is celebrating a birthday today is 1/365.

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Q: More than 30 percent of the results from major search engines for

More than 30 percent of the results from major search engines for the keyword phrase “ring tone” are fake pages created by spammers.

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the data on housing starts. Modify the default colors, fonts, etc., to make the display effective. (b) Describe the pattern, if any.

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the skier/snowboarder data. Modify the default colors, fonts, etc., to make the display effective. (b) Describe the pattern, if any.

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Q: An ad for a cell phone service claims that it’s percent of

An ad for a cell phone service claims that it’s percent of “dropped calls” was significantly lower than that of its main competitor. In the fi ne print, the percents were given as 1.2 percent versus 1...

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Q: Calculate each Poisson probability: a. More than 10

Calculate each Poisson probability: a. More than 10 arrivals with λ = 8.0. b. No more than 5 arrivals with λ = 4.0. c. At least 2 arrivals with λ = 5.0

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Q: Vail Resorts uses various types of scales and questions on their surveys

Vail Resorts uses various types of scales and questions on their surveys. Here is a question from their guest satisfaction survey that uses a five-point scale. (a) Would the measurement level for the...

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Q: A recent study of 231,164 New Jersey heart attack patients

A recent study of 231,164 New Jersey heart attack patients showed that those admitted on a weekday had a 12.0 percent death rate in the next three years, compared with 12.9 percent for those admitted...

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Q: Would you use a sample or a census to measure each of

Would you use a sample or a census to measure each of the following? Why? a. The model years of the cars driven by each of your five closest friends. b. The model years of the cars driven by each stu...

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the data on housing starts. Modify the default colors, fonts, etc., to make the display effective. (b) Describe the pattern, if any.

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Q: Would you use a sample or a census to measure each of

Would you use a sample or a census to measure each of the following? Why? If you are uncertain, explain the issues. a. The mean time battery life of your laptop computer in continuous use. b. The num...

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Q: The target population is all stocks in the S&P 500

The target population is all stocks in the S&P 500 index. Is each of the following a parameter or a statistic? a. The average price/earnings ratio for all 500 stocks in the S&P index. b. The proporti...

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Q: Under a recent U.S. Food and Drug Administration (

Under a recent U.S. Food and Drug Administration (FDA) standard for food contaminants, 3.5 ounces of tomato sauce can have up to 30 fly eggs, and 11 ounces of wheat flour can contain 450 insect fragme...

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Q: Suppose you want to know the ages of moviegoers who attend the

Suppose you want to know the ages of moviegoers who attend the latest Hunger Games movie. What kind of sample is it if you (a) survey the first 20 persons to emerge from the theater, (b) survey every...

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Q: Ergonomics is the science of making sure that human surroundings are adapted

Ergonomics is the science of making sure that human surroundings are adapted to human needs. How could statistics play a role in the following: a. Choosing the height of an office chair so that 95 pe...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data for bottled water sales for 10 weeks, placing Price on the X-axis and Units Sold on the Y-axis. Add titles and modify the default colors, fonts, etc.,...

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Q: Calculate each Poisson probability: a. Fewer than 4

Calculate each Poisson probability: a. Fewer than 4 arrivals with λ = 5.8. b. At least 3 arrivals with λ = 4.8. c. At most 9 arrivals with λ = 7.0.

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Q: A recent study showed that women who lived near a freeway had

A recent study showed that women who lived near a freeway had an unusually high rate of rheumatoid arthritis. Sarah said, “They should move away from freeways.” Is there a fallacy in Sarah’s reasoning...

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Q: “Lacrosse helmets are not needed,” said Tom. “None

“Lacrosse helmets are not needed,” said Tom. “None of the guys on my team have ever had head injuries.” Is there a fallacy in Tom’s reasoning? Explain.

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Q: A European study of thousands of men found that the PSA screening

A European study of thousands of men found that the PSA screening for prostate cancer reduced the risk of a man’s dying from prostate cancer from 3.0 percent to 2.4 percent. “But it’s already a small...

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the skier/snowboarder data. Modify the default colors, fonts, etc., to make the display effective. (b) Describe the pattern, if any.

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Q: A research study showed that adolescents who watched more than 4 hours

A research study showed that adolescents who watched more than 4 hours of TV per day were more than five times as likely to start smoking as those who watched less than 2 hours a day. The researchers...

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Q: A study of 40 U.S. cardiac care centers showed

A study of 40 U.S. cardiac care centers showed the following ratios of nurses to beds. (a) Prepare a dot plot. (b) Prepare a frequency distribution and histogram (you may either specify the bins yours...

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Q: The first Rose Bowl (football) was played in 1902.

The first Rose Bowl (football) was played in 1902. The next was not played until 1916, but a Rose Bowl has been played every year since then. The margin of victory in each of the 95 Rose Bowls from 19...

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Q: Which type of data (categorical, discrete numerical, continuous numerical

Which type of data (categorical, discrete numerical, continuous numerical) is each of the following variables? a. Age of a randomly chosen tennis player in the Wimbledon tennis tournament. b. Nationa...

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Q: Which type of data (categorical, discrete numerical, continuous numerical

Which type of data (categorical, discrete numerical, continuous numerical) is each of the following variables? a. Number of spectators at a randomly chosen Wimbledon tennis match. b. Water consumptio...

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Q: Which measurement level (nominal, ordinal, interval, ratio)

Which measurement level (nominal, ordinal, interval, ratio) is each of the following variables? a. A customer’s ranking of five new hybrid vehicles. b. Noise level 100 meters from the Dan Ryan Expres...

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Q: According to J.D. Power and Associates’ 2006 Initial Quality

According to J.D. Power and Associates’ 2006 Initial Quality Study, consumers reported on average 1.7 problems per vehicle with new 2006 Volkswagens. In a randomly selected new Volkswagen, find the pr...

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Q: Which measurement level (nominal, ordinal, interval, ratio)

Which measurement level (nominal, ordinal, interval, ratio) is each of the following variables? a. Number of annual office visits by a particular Medicare subscriber. b. Daily caffeine consumption by...

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Q: Below are five questions from a survey of MBA students. Answers

Below are five questions from a survey of MBA students. Answers were written in the blank at the left of each question. For each question, state the data type (categorical, discrete numerical, or cont...

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Q: Below are five questions from a survey of MBA students. Answers

Below are five questions from a survey of MBA students. Answers were written in the blank at the left of each question. For each question, state the data type (categorical, discrete numerical, or cont...

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Q: Below are five questions from a survey of MBA students. Answers

Below are five questions from a survey of MBA students. Answers were written in the blank at the left of each question. For each question, state the data type (categorical, discrete numerical, or cont...

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Q: Identify the following data as either time series or cross-sectional

Identify the following data as either time series or cross-sectional. a. The 2014 CEO compensation of the 500 largest U.S. companies. b. The annual compensation for the CEO of Coca-Cola Enterprises f...

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Q: Identify the following data as either time series or cross-sectional

Identify the following data as either time series or cross-sectional. a. The number of rooms booked each night for the month of January 2014 at a Vail Resorts hotel. b. The amount spent on books at t...

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Q: Would you use a sample or a census to measure each of

Would you use a sample or a census to measure each of the following? Why? If you are uncertain, explain the issues. a. The number of cans of Campbell’s soup on your local supermarket’s shelf today at...

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Q: Would you use a sample or census to measure each of the

Would you use a sample or census to measure each of the following? a. The number of workers currently employed by Campbell Soup Company. b. The average price of a can of Campbell’s Cream of Mushroom...

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Q: Is each of the following a parameter or a statistic? If

Is each of the following a parameter or a statistic? If you are uncertain, explain the issues. a. The number of cans of Campbell’s soup sold last week at your local supermarket. b. The proportion of...

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Q: Is each of the following a parameter or statistic?

Is each of the following a parameter or statistic? a. The number of visits to a pediatrician’s office last week. b. The number of copies of John Grisham’s most recent novel sold to date. c. The total...

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Q: At an outpatient mental health clinic, appointment cancellations occur at a

At an outpatient mental health clinic, appointment cancellations occur at a mean rate of 1.5 per day on a typical Wednesday. Let X be the number of cancellations on a particular Wednesday. (a) Justify...

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Q: Recently, researchers estimated that 76.8 percent of global e

Recently, researchers estimated that 76.8 percent of global e-mail traffic was spam. Could a census be used to update this estimate? Why or why not?

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Q: A certain health maintenance organization (HMO) is studying its daily

A certain health maintenance organization (HMO) is studying its daily office routine. They collect information on three variables: the number of patients who visit during a day, the patient’s complain...

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Q: There are 327 official ports of entry in the United States.

There are 327 official ports of entry in the United States. The Department of Homeland Security selects 15 ports of entry at random to be audited for compliance with screening procedures of incoming t...

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Q: The IRS estimates that the average taxpayer spent 3.7 hours

The IRS estimates that the average taxpayer spent 3.7 hours preparing Form 1040 to fi le a tax return. Could a census be used to update this estimate for the most recent tax year? Why or why not?

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Q: The General Accounting Office conducted random testing of retail gasoline pumps in

The General Accounting Office conducted random testing of retail gasoline pumps in Michigan, Missouri, Oregon, and Tennessee. The study concluded that 49 percent of gasoline pumps nationwide are misla...

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Q: Arsenic (a naturally occurring, poisonous metal) in home water

Arsenic (a naturally occurring, poisonous metal) in home water wells is a common threat. (a) What sampling method would you use to estimate the arsenic levels in wells in a rural county to see whether...

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Q: Would you expect Starbucks to use a sample or census to measure

Would you expect Starbucks to use a sample or census to measure each of the following? Explain. a. The percentage of repeat customers at a certain Starbucks on Saturday mornings. b. The number of cha...

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Q: Would you expect Noodles & Company to use a sample or census

Would you expect Noodles & Company to use a sample or census to measure each of the following? Explain. a. The annual average weekly revenue of each Noodles restaurant. b. The average number of weekl...

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Q: A financial magazine publishes an annual list of major stock funds.

A financial magazine publishes an annual list of major stock funds. Last year, the list contained 1,699 funds. What method would you recommend to obtain a sample of 20 stock funds to estimate the 10-y...

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Q: Examine each of the following statistics. Which sampling method was most

Examine each of the following statistics. Which sampling method was most likely to have been used (simple random, systematic, stratified, cluster)? a. A survey showed that 30 percent of U.S. business...

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Q: On hot, sunny, summer days, Jane rents inner tubes

On hot, sunny, summer days, Jane rents inner tubes by the river that runs through her town. Based on her past experience, she has assigned the following probability distribution to the number of tubes...

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Q: The National Claims History (NCH) contains records for 999,

The National Claims History (NCH) contains records for 999,645 Medicare patients who were discharged from acute care hospitals in October 2008. The Department of Health and Human Services performed a...

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Q: Prior to starting a recycling program, a city decides to measure

Prior to starting a recycling program, a city decides to measure the quantity of garbage produced by single-family homes in various neighborhoods. This experiment will require weighing garbage on the...

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Q: (a) For each data set, calculate the mean,

(a) For each data set, calculate the mean, median, and mode. (b) Which, if any, of these three measures is the weakest indicator of a “typical” data value? Why? a. Number of e-mail accounts (12 stude...

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Q: If the mean asset turnover for retail firms is 2.02

If the mean asset turnover for retail firms is 2.02 with a standard deviation of 0.22, without assuming a normal distribution, within what range will at least 75% of retail firms’ asset turnover fall?...

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Q: For each data set: (a) Find the mean,

For each data set: (a) Find the mean, median, and mode. (b) Which, if any, of these three measures is the weakest indicator of a “typical” data value? Why?

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Q: During a rock concert, the noise level (in decibels)

During a rock concert, the noise level (in decibels) in front row seats has a mean of 95 dB with a standard deviation of 8 dB. Without assuming a normal distribution, find the minimum percentage of no...

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Q: Bags of jelly beans have a mean weight of 396 gm with

Bags of jelly beans have a mean weight of 396 gm with a standard deviation of 5 gm. Use Chebyshev’s Theorem to find a lower bound for the number of bags in a sample of 200 that weigh between 386 and 4...

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Q: Based on experience, the Ball Corporation’s aluminum can manufacturing facility in

Based on experience, the Ball Corporation’s aluminum can manufacturing facility in Ft. Atkinson, Wisconsin, knows that the metal thickness of incoming shipments has a mean of 0.2731 mm with a standard...

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Q: SAT scores for the entering class of 2010 at Oxnard University were

SAT scores for the entering class of 2010 at Oxnard University were normally distributed with a mean of 1340 and a standard deviation of 90. Bob’s SAT score was 1430. (a) Find Bob’s standardized z-sco...

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Q: Find the data value that corresponds to each of the following z

Find the data value that corresponds to each of the following z-scores. a. Final exam scores: Allison’s z-score = 2.30, μ = 74, σ = 7 b. Weekly grocery bill: James’ z-score = 21.45, μ = $53, σ = $12...

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Q: Three percent of the letters placed in a certain postal drop box

Three percent of the letters placed in a certain postal drop box have incorrect postage. Suppose 200 letters are mailed. (a) For this binomial, what is the expected number with incorrect postage? (b)...

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Q: The average time a Boulder High varsity lacrosse player plays in a

The average time a Boulder High varsity lacrosse player plays in a game is 30 minutes with a standard deviation of 7 minutes. Nolan’s playing time in last week’s game against Fairview was 48 minutes....

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Q: The number of blueberries in a blueberry muffin baked by Earth Harvest

The number of blueberries in a blueberry muffin baked by Earth Harvest Bakeries can range from 18 to 30 blueberries. (a) Use the Empirical Rule to estimate the standard deviation of the number of blue...

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Q: A random sample of 21 nickels measured with a very accurate micrometer

A random sample of 21 nickels measured with a very accurate micrometer showed a mean diameter of 0.834343 inch with a standard deviation of 0.001886 inch. (a) Why would nickel diameters vary? (b) Cons...

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Q: Use Excel to generate 1,000 random integers in the range

Use Excel to generate 1,000 random integers in the range 1 through 5. (a) What are the expected mean and standard deviation? (b) Show the Excel formula you used.

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Q: A random sample of 10 miniature Tootsie Rolls was taken from a

A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were (a) Construct a 90 percent confidence interval for the...

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Q: Consider the Bernoulli model. What would be a typical probability of

Consider the Bernoulli model. What would be a typical probability of success (π) for (a) free throw shooting by a good college basketball player? (b) Hits by a good baseball batter? (c) Passes complet...

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Q: There is a 14 percent chance that a Noodles & Company customer

There is a 14 percent chance that a Noodles & Company customer will order bread with the meal. Use Excel to find the probability that in a sample of 10 customers (a) more than five will order bread;...

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Q: A sample of 20 pages was taken from a Yellow Pages directory

A sample of 20 pages was taken from a Yellow Pages directory. On each page, the mean area devoted to display ads was measured (a display ad is a large block of multicolored illustrations, maps, and te...

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Q: The probability that an American CEO can transact business in a foreign

The probability that an American CEO can transact business in a foreign language is .20. Ten American CEOs are chosen at random. (a) What is the probability that none can transact business in a foreig...

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Q: In a certain Kentucky Fried Chicken franchise, half of the customers

In a certain Kentucky Fried Chicken franchise, half of the customers typically request “crispy” instead of “original.” (a) What is the probability that none of the next four customers will request “cr...

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Q: (a) State the values that X can assume in each

(a) State the values that X can assume in each hypergeometric scenario. (b) Use the hypergeometric PDF formula to find the probability requested. (c) Check your answer by using Excel. i. N = 10, n =...

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Q: On average, 40 percent of U.S. beer drinkers

On average, 40 percent of U.S. beer drinkers order light beer. (a) What is the probability that none of the next eight customers who order beer will order light beer? (b) That one customer will? (c) T...

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Q: Passengers using New York’s MetroCard system must swipe the card at a

Passengers using New York’s MetroCard system must swipe the card at a rate between 10 and 40 inches per second, or else the card must be re-swiped through the card reader. Research shows that actual s...

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Q: Tired of careless spelling and grammar, a company decides to administer

Tired of careless spelling and grammar, a company decides to administer a test to all job applicants. The test consists of 20 sentences. Applicants must state whether each sentence contains any gramma...

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Q: The default rate on government-guaranteed student loans at a certain

The default rate on government-guaranteed student loans at a certain private 4-year institution is 7 percent. The college extends 10 such loans. (a) What is the probability that none of them will defa...

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Q: The weekly demand for Papa Chubby’s pizzas on a Friday night is

The weekly demand for Papa Chubby’s pizzas on a Friday night is a random variable with mean 235 and standard deviation 10. Find the value(s) of X for each event. Show your work. a. Lowest 50 percent...

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Q: The amounts spent by customers at a Noodles & Company restaurant during

The amounts spent by customers at a Noodles & Company restaurant during lunch are normally distributed with a mean equal to $7.00 and a standard deviation equal to $0.35. (a) What amount is the first...

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Q: The length of a Colorado brook trout is normally distributed. (

The length of a Colorado brook trout is normally distributed. (a) What is the probability that a brook trout’s length exceeds the mean? (b) Exceeds the mean by at least 1 standard deviation? (c) Excee...

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Q: A small feeder airline knows that the probability is .10 that

A small feeder airline knows that the probability is .10 that a reservation holder will not show up for its daily 7:15 a.m. flight into a hub airport. The flight carries 10 passengers. (a) If the flig...

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Q: Although television HDTV converters are tested before they are placed in the

Although television HDTV converters are tested before they are placed in the installer’s truck, the installer knows that 20 percent of them still won’t work properly. The driver must install eight con...

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Q: Chlorine concentration in a municipal water supply is a uniformly distributed random

Chlorine concentration in a municipal water supply is a uniformly distributed random variable that ranges between 0.74 ppm and 0.98 ppm. (a) What is the mean chlorine concentration? (b) The standard...

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Q: A statistics textbook chapter contains 60 exercises, 6 of which are

A statistics textbook chapter contains 60 exercises, 6 of which are essay questions. A student is assigned 10 problems. Define X to be the number of essay questions the student receives. (a) Use Excel...

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Q: Why might the number of calls received per minute at a fire

Why might the number of calls received per minute at a fire station not be a Poisson event?

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Q: Software filters rely heavily on “blacklists” (lists of known

Software filters rely heavily on “blacklists” (lists of known “phishing” URLs) to detect fraudulent e-mails. But such filters typically catch only 20 percent of phishing URLs. Jason receives 16 phishi...

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Q: The weekly demand for Baked Lay’s potato chips at a certain Subway

The weekly demand for Baked Lay’s potato chips at a certain Subway sandwich shop is a random variable with mean 450 and standard deviation 80. Find the value(s) of X for each event. Show your work. a...

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Q: In a major league baseball game, the average is 1.

In a major league baseball game, the average is 1.0 broken bat per game. Find the probability of (a) no broken bats in a game; (b) at least 2 broken bats.

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Q: In a certain microwave oven on the high power setting, the

In a certain microwave oven on the high power setting, the time it takes a randomly chosen kernel of popcorn to pop is normally distributed with a mean of 140 seconds and a standard deviation of 25 se...

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Q: Dave the jogger runs the same route every day (about 2

Dave the jogger runs the same route every day (about 2.2 miles). On 18 consecutive days, he recorded the number of steps using a pedometer. The results were (a) Construct a 95 percent confidence int...

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Q: At an outpatient mental health clinic, appointment cancellations occur at a

At an outpatient mental health clinic, appointment cancellations occur at a mean rate of 1.5 per day on a typical Wednesday. Let X be the number of cancellations on a particular Wednesday. (a) Justify...

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Q: A sample of 40 CDs from a student’s collection showed a mean

A sample of 40 CDs from a student’s collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes. (a) Construct a 95 percent confidence interval for the mean. (b) Why mi...

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Q: In a certain automobile manufacturing paint shop, paint defects on the

In a certain automobile manufacturing paint shop, paint defects on the hood occur at a mean rate of 0.8 defect per square meter. A hood on a certain car has an area of 3 square meters. (a) Justify the...

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Q: Jim’s systolic blood pressure is a random variable with a mean of

Jim’s systolic blood pressure is a random variable with a mean of 145 mmHg and a standard deviation of 20 mmHg. For Jim’s age group, 140 is the threshold for high blood pressure. (a) If Jim’s systoli...

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Q: Fifty employee travel expense reimbursement vouchers were filed last quarter in the

Fifty employee travel expense reimbursement vouchers were filed last quarter in the finance department at Ramjac Corporation. Of these, 20 contained errors. A corporate auditor inspects five vouchers...

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Q: A “rogue wave” (one far larger than others surrounding

A “rogue wave” (one far larger than others surrounding a ship) can be a threat to ocean-going vessels (e.g., naval vessels, container ships, oil tankers). The European Centre for Medium Range Weather...

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Q: In Northern Yellowstone Lake, earthquakes occur at a mean rate of

In Northern Yellowstone Lake, earthquakes occur at a mean rate of 1.2 quakes per year. Let X be the number of quakes in a given year. (a) Justify the use of the Poisson model. (b) What is the probabil...

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Q: On New York’s Verrazano Narrows bridge, traffic accidents occur at a

On New York’s Verrazano Narrows bridge, traffic accidents occur at a mean rate of 2.0 crashes per day. Let X be the number of crashes in a given day. (a) Justify the use of the Poisson model. (b) What...

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Q: Leaks occur in a pipeline at a mean rate of 1 leak

Leaks occur in a pipeline at a mean rate of 1 leak per 1,000 meters. In a 2,500-meter section of pipe, what is the probability of (a) no leaks? (b) Three or more leaks? (c) What is the expected number...

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Q: How many riders would there have to be on a bus to

How many riders would there have to be on a bus to yield (a) a 50 percent probability that at least two will have the same birthday? (b) A 75 percent probability? Hint: Use the Learning Stats demonstr...

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Q: Among live deliveries, the probability of a twin birth is .

Among live deliveries, the probability of a twin birth is .02. (a) In 200 live deliveries, how many would be expected to have twin births? (b) What is the probability of no twin births? (c) One twin b...

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Q: The probability is .03 that a passenger on United Airlines Flight

The probability is .03 that a passenger on United Airlines Flight 9841 is a Platinum flyer (50,000 miles per year). If 200 passengers take this flight, use Excel to find the binomial probability of (a...

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Q: The probability of being “bumped” (voluntarily or involuntarily)

The probability of being “bumped” (voluntarily or involuntarily) on a U.S. airline was .00128. The average number of passengers traveling through Denver International Airport each hour is 5,708. (a) W...

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Q: On average, 2 percent of all persons who are given a

On average, 2 percent of all persons who are given a breathalyzer test by the state police pass the test (blood alcohol under .08 percent). Suppose that 500 breathalyzer tests are given. (a) What is t...

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Q: The probability of an incorrect call by an NFL referee is .

The probability of an incorrect call by an NFL referee is .025 (e.g., calling a pass complete, but the decision reversed on instant replays). In a certain game, there are 150 plays. (a) What is the pr...

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Q: On hot, sunny, summer days, Jane rents inner tubes

On hot, sunny, summer days, Jane rents inner tubes by the river that runs through her town. Based on her past experience, she has assigned the following probability distribution to the number of tubes...

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Q: On the midnight shift, the number of patients with head trauma

On the midnight shift, the number of patients with head trauma in an emergency room has the probability distribution shown below. (a) Calculate the mean and standard deviation. (b) Describe the shape...

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Q: Nationwide, the probability that a rental car is from Hertz is

Nationwide, the probability that a rental car is from Hertz is 25 percent. In a sample of 100 rental cars, what is the probability that fewer than 20 are from Hertz?

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Q: A multiple-choice exam has 100 questions. Each question has

A multiple-choice exam has 100 questions. Each question has four choices. (a) What minimum score should be required to reduce the chance of passing by random guessing to 5 percent? (b) To 1 percent? (...

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Q: The probability that a certain kind of flower seed will germinate is

The probability that a certain kind of flower seed will germinate is .80. (a) If 200 seeds are planted, what is the probability that fewer than 150 will germinate? (b) That at least 150 will germinate...

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Q: On a cold morning the probability is .02 that a given

On a cold morning the probability is .02 that a given car will not start in the small town of Eureka. Assume that 1,500 cars are started each cold morning. (a) What is the probability that at least 25...

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Q: At a certain fire station, false alarms are received at a

At a certain fire station, false alarms are received at a mean rate of 0.2 per day. In a year, what is the probability that fewer than 60 false alarms are received?

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Q: The probability of being in a car accident when driving more than

The probability of being in a car accident when driving more than 10 miles over the speed limit in a residential neighborhood is .06. Of the next 1,000 cars that pass through a particular neighborhood...

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Q: Among live deliveries, the probability of a twin birth is .

Among live deliveries, the probability of a twin birth is .02. (a) In 2,000 live deliveries, what is the probability of at least 50 twin births? (b) Fewer than 35?

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Q: In CABG surgery, there is a .00014 probability of a

In CABG surgery, there is a .00014 probability of a retained foreign body (e.g., a sponge or a surgical instrument) left inside the patient. (a) In 100,000 CABG surgeries, what is the expected number...

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Q: A biometric security device using fingerprints erroneously refuses to admit 1 in

A biometric security device using fingerprints erroneously refuses to admit 1 in 1,000 authorized persons from a facility containing classified information. The device will erroneously admit 1 in 1,00...

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Q: Dolon Web Security Consultants requires all job applicants to submit to a

Dolon Web Security Consultants requires all job applicants to submit to a test for illegal drugs. If the applicant has used illegal drugs, the test has a 90 percent chance of a positive result. If the...

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Q: A medical laboratory receives 40 blood specimens to check for HIV.

A medical laboratory receives 40 blood specimens to check for HIV. Eight actually contain HIV. A worker is accidentally exposed to five specimens. (a) Use Excel to calculate the entire hypergeometric...

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Q: A test for ovarian cancer has a 5 percent rate of false

A test for ovarian cancer has a 5 percent rate of false positives and a 0 percent rate of false negatives. On average, 1 in every 2,500 American women over age 35 actually has ovarian cancer. If a wom...

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Q: The amount of fill in a half-liter (500 ml

The amount of fill in a half-liter (500 ml) soft drink bottle is normally distributed. The process has a standard deviation of 5 ml. The mean is adjustable. (a) Where should the mean be set to ensure...

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Q: The length of a certain kind of Colorado brook trout is normally

The length of a certain kind of Colorado brook trout is normally distributed with a mean of 12.5 inches and a standard deviation of 1.2 inches. What minimum size limit should the Department of Natural...

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Q: Times for a surgical procedure are normally distributed. There are two

Times for a surgical procedure are normally distributed. There are two methods. Method A has a mean of 28 minutes and a standard deviation of 4 minutes, while method B has a mean of 32 minutes and a s...

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Q: The length of a brook trout is normally distributed. Two brook

The length of a brook trout is normally distributed. Two brook trout are caught. (a) What is the probability that both exceed the mean? (b) Neither exceeds the mean? (c) One is above the mean and o...

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Q: A statistics exam was given. Calculate the percentile for each of

A statistics exam was given. Calculate the percentile for each of the following four students. a. John’s z-score was -1.62. b. Mary’s z-score was 0.50. c. Zak’s z-score was 1.79. d. Frieda’s z-score...

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Q: Are the following statements true or false? Explain your reasoning.

Are the following statements true or false? Explain your reasoning. a. “If we see a standardized z-value beyond 63, the variable cannot be normally distributed.” b. “If X and Y are two normally distr...

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Q: John can take either of two routes (A or B)

John can take either of two routes (A or B) to LAX airport. At midday on a typical Wednesday the travel time on either route is normally distributed with parameters μA = 54 minutes, σA = 6 minutes, μB...

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Q: In a sample of 100 Planter’s Mixed Nuts, 19 were found

In a sample of 100 Planter’s Mixed Nuts, 19 were found to be almonds. (a) Construct a 90 percent confidence interval for the true proportion of almonds. (b) May normality be assumed? Explain. (c) What...

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Q: Discuss why you would or would not expect each of the following

Discuss why you would or would not expect each of the following variables to be normally distributed. Hint: Would you expect a single central mode and tapering tails? Would the distribution be roughly...

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Q: (a) Check whether the binomial approximation is acceptable in each

(a) Check whether the binomial approximation is acceptable in each of the following hypergeometric situations. (b) Find the binomial approximation (using Appendix A) for each probability requested. (c...

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Q: Why might the following not be normally distributed? (a)

Why might the following not be normally distributed? (a) The time it takes you to drive to the airport. (b) The annual income for a randomly chosen Major League Baseball player. (c) The annual hurrica...

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Q: Write the Excel binomial formula for each probability. a

Write the Excel binomial formula for each probability. a. Three successes in 20 trials with a 30 percent chance of success. b. Seven successes in 50 trials with a 10 percent chance of success. c. Six...

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Q: Scores on a certain accounting exam were normally distributed with a mean

Scores on a certain accounting exam were normally distributed with a mean of 75 and a standard deviation of 7. Find the percentile for each individual using Excel’s =NORM.S.DIST function. (a) Bob’s sc...

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Q: A random sample of 30 lunch orders at Noodles and Company showed

A random sample of 30 lunch orders at Noodles and Company showed a standard deviation of $5.31. Find the 90 percent confidence interval for the population standard deviation. Use Excel to obtain X2L =...

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Q: Experience indicates that 8 percent of the pairs of men’s trousers dropped

Experience indicates that 8 percent of the pairs of men’s trousers dropped off for dry cleaning will have an object in the pocket that should be removed before cleaning. Suppose that 14 pairs of pants...

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Q: A study by the Parents’ Television Council showed that 80 percent of

A study by the Parents’ Television Council showed that 80 percent of movie commercials aired on network television between 8 and 9 p.m. (the prime family viewing hour) were for R-rated films. (a) Find...

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Q: Write the Excel formula for each Poisson probability, using a mean

Write the Excel formula for each Poisson probability, using a mean arrival rate of 10 arrivals per hour. a. Seven arrivals. b. Three arrivals. c. Fewer than five arrivals. d. At least 11 arrivals....

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Q: The caffeine content of a cup of home-brewed coffee is

The caffeine content of a cup of home-brewed coffee is a normally distributed random variable with a mean of 115 mg with a standard deviation of 20 mg. (a) What is the probability that a randomly chos...

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Q: The fracture strength of a certain type of manufactured glass is normally

The fracture strength of a certain type of manufactured glass is normally distributed with a mean of 579 MPa with a standard deviation of 14 MPa. (a) What is the probability that a randomly chosen sam...

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Q: Tire pressure in a certain car is a normally distributed random variable

Tire pressure in a certain car is a normally distributed random variable with mean 30 psi (pounds per square inch) and standard deviation 2 psi. The manufacturer’s recommended correct inflation range...

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Q: Two hundred employee travel expense reimbursement vouchers were filed last year in

Two hundred employee travel expense reimbursement vouchers were filed last year in the finance department at Ramjac Corporation. Of these, 20 contained errors. A corporate auditor audits a sample of f...

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Q: Noodles & Company wants to estimate the percent of customers who order

Noodles & Company wants to estimate the percent of customers who order dessert, with 95 percent confidence and an error of ±10%. What is the required sample size?

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Q: Lunch customers arrive at a Noodles & Company restaurant at an average

Lunch customers arrive at a Noodles & Company restaurant at an average rate of 2.8 per minute. Define X to be the number of customers to arrive during a randomly selected minute during the lunch hour...

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Q: Shower temperature at the Oxnard Health Club showers is regulated automatically.

Shower temperature at the Oxnard Health Club showers is regulated automatically. The heater kicks in when the temperature falls to 998F and shuts off when the temperature reaches 1078F. Water temperat...

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Q: In the last 50 years, the average number of deaths due

In the last 50 years, the average number of deaths due to alligators in Florida is 0.3 death per year. Assuming no change in this average, in a given year find the probability of (a) no alligator deat...

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Q: In a recent year, potentially dangerous commercial aircraft incidents (e

In a recent year, potentially dangerous commercial aircraft incidents (e.g., near collisions) averaged 1.2 per 100,000 flying hours. Let X be the number of incidents in a 100,000-hour period. (a) Just...

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Q: The length of a time-out during a televised professional football

The length of a time-out during a televised professional football game is normally distributed with a mean of 84 seconds and a standard deviation of 10 seconds. If the network runs consecutive commerc...

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Q: Car security alarms go off at a mean rate of 3.

Car security alarms go off at a mean rate of 3.8 per hour in a large Costco parking lot. Find the probability that in an hour there will be (a) no alarms; (b) fewer than four alarms; and (c) more than...

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Q: Demand for residential electricity at 6:00 p.m.

Demand for residential electricity at 6:00 p.m. on the first Monday in October in Santa Theresa County is normally distributed with a mean of 4,905 MW (megawatts) and a standard deviation of 355 MW. D...

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Q: Past insurance company audits have found that 2 percent of dependents claimed

Past insurance company audits have found that 2 percent of dependents claimed on an employee’s health insurance actually are ineligible for health benefits. An auditor examines a random sample of 7 cl...

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Q: Procyon Manufacturing produces tennis balls. Their manufacturing process has a mean

Procyon Manufacturing produces tennis balls. Their manufacturing process has a mean ball weight of 2.035 ounces with a standard deviation of 0.03 ounce. Regulation tennis balls are required to have a...

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Q: A law enforcement agency processes 500 background checks for firearms purchasers.

A law enforcement agency processes 500 background checks for firearms purchasers. Fifty applicants are convicted felons. Through a clerk’s error, 10 applicants are approved without checking for felony...

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Q: Tests show that, on average, the Li-ion Hitachi

Tests show that, on average, the Li-ion Hitachi stick driver can drive 207 drywall screws on a single charge. Bob needs to drive 230 drywall screws. If the standard deviation is 14 screws, find the pr...

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Q: The time it takes to give a man a shampoo and haircut

The time it takes to give a man a shampoo and haircut is normally distributed with mean 22 minutes and standard deviation 3 minutes. Customers are scheduled every 30 minutes. (a) What is the probabili...

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Q: If the weight (in grams) of cereal in a box

If the weight (in grams) of cereal in a box of Lucky Charms is N(470,5), what is the probability that the box will contain less than the advertised weight of 453 g?

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Q: Vail Resorts would like to send a survey to their guests asking

Vail Resorts would like to send a survey to their guests asking about their satisfaction with the new 2009 website design. They would like to have a margin of error of ±5 percent on responses with 95...

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Q: Statistics students were asked to go home and fill a 1-

Statistics students were asked to go home and fill a 1-cup measure with raisin bran, tap the cup lightly on the counter three times to settle the contents, if necessary add more raisin bran to bring t...

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Q: Twenty-five blood samples were selected by taking every seventh blood

Twenty-five blood samples were selected by taking every seventh blood sample from racks holding 187 blood samples from the morning draw at a medical center. (a) Calculate the FPCF for this sample. (b)...

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Q: Sixteen owners of 2010 Audi A4 sedans kept track of their average

Sixteen owners of 2010 Audi A4 sedans kept track of their average fuel economy for a month. The results are shown below. (a) Construct a 95 percent confidence interval for the mean. (b) What factor(s)...

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Q: Twenty-five blood samples were selected by taking every seventh blood

Twenty-five blood samples were selected by taking every seventh blood sample from racks holding 187 blood samples from the morning draw at a medical center. The white blood count (WBC) was measured us...

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Q: Twenty-one warranty repairs were selected from a population of 126

Twenty-one warranty repairs were selected from a population of 126 by selecting every sixth item. The population consisted of “loose, not attached” minivan electrical wires (one of several electrical...

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Q: A pediatrician’s records showed the mean height of a random sample of

A pediatrician’s records showed the mean height of a random sample of 25 girls at age 12 months to be 29.530 inches with a standard deviation of 1.0953 inches. (a) Construct a 95 percent confidence in...

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Q: Four hundred automobiles are to be inspected for California emissions compliance.

Four hundred automobiles are to be inspected for California emissions compliance. Of these, 320 actually are compliant but 80 are not. A random sample of 6 cars is chosen. (a) Justify the use of the b...

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Q: A random sample of 10 exam scores showed a standard deviation of

A random sample of 10 exam scores showed a standard deviation of 7.2 points. Find the 95 percent confidence interval for the population standard deviation. Use Appendix E to obtain the values of X2L a...

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Q: During the Rose Bowl, the length (in seconds) of

During the Rose Bowl, the length (in seconds) of 12 randomly chosen commercial breaks during timeouts (following touchdown, turnover, field goal, or punt) were Assuming a normal population, construc...

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Q: The Environmental Protection Agency (EPA) requires that cities monitor over

The Environmental Protection Agency (EPA) requires that cities monitor over 80 contaminants in their drinking water. Samples from the Lake Huron Water Treatment Plant gave the results shown here. Only...

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Q: A study showed that fourteen of 180 publicly traded business services companies

A study showed that fourteen of 180 publicly traded business services companies failed a test for compliance with Sarbanes-Oxley requirements for financial records and fraud protection. Assuming that...

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Q: How “decaffeinated” is decaffeinated coffee? If a researcher wants

How “decaffeinated” is decaffeinated coffee? If a researcher wants to estimate the mean caffeine content of a cup of Starbucks’ decaffeinated espresso with 98 percent confidence and an error of ±0.1 m...

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Q: Junior Achievement and Deloitte commissioned a “teen ethics poll” of

Junior Achievement and Deloitte commissioned a “teen ethics poll” of 787 students aged 13–18, finding that 29 percent felt inadequately prepared to make ethical judgments. (a) Assuming that this was a...

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Q: A random sample of 30 cans of Del Vino crushed tomatoes revealed

A random sample of 30 cans of Del Vino crushed tomatoes revealed a mean weight of 798.3 grams (excluding the juice). The can-filling process for Del Vino crushed tomatoes has a known standard deviatio...

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Q: A poll of 125 college students who watch The Big Bang Theory

A poll of 125 college students who watch The Big Bang Theory showed that 83 of them usually watch on a mobile device (e.g., laptop). (a) Assuming that this was a random sample, construct a 90 percent...

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Q: A survey of 4,581 U.S. households that

A survey of 4,581 U.S. households that owned a mobile phone found that 58 percent are satisfied with the coverage of their cellular phone provider. Assuming that this was a random sample, construct a...

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Q: A “teen ethics poll” was commissioned by Junior Achievement and

A “teen ethics poll” was commissioned by Junior Achievement and Deloitte. The survey by Harris Interactive surveyed 787 students aged 13–18. (a) Assuming that this was a random sample of all students...

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Q: July sales for Melodic Kortholt, Ltd., average μ1 = $

July sales for Melodic Kortholt, Ltd., average μ1 = $9,500 with σ1 2 = $1,250. August sales average μ2 = $7,400 with σ2 2 = $1,425. September sales average μ3 = $8,600 with σ3 2 = $1,610. (a) Find the...

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Q: Biting an unpopped kernel of popcorn hurts! As an experiment,

Biting an unpopped kernel of popcorn hurts! As an experiment, a self-confessed connoisseur of cheap popcorn carefully counted 773 kernels and put them in a popper. After popping, the unpopped kernels...

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Q: A sample of 213 newspaper tire ads from several Sunday papers showed

A sample of 213 newspaper tire ads from several Sunday papers showed that 98 contained a low-price guarantee (offer to “meet or beat any price”). (a) Assuming that this was a random sample, construct...

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Q: A physician’s billing office conducted a random check of patient records and

A physician’s billing office conducted a random check of patient records and found that 36 of 50 patients had changed insurance plans within the past year. Construct a 90 percent confidence interval f...

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Q: Of 250 college students taking a statistics class, 4 reported an

Of 250 college students taking a statistics class, 4 reported an allergy to peanuts. (a) Is the criterion for normality of p met? (b) Assuming that this was a random sample, use MINITAB to construct a...

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Q: (a) A poll of 2,277 likely voters was

(a) A poll of 2,277 likely voters was conducted on the president’s performance. Approximately what margin of error would the approval rating estimate have? (b) The poll showed that 44 percent approved...

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Q: To determine the proportion of taxpayers who prefer filing tax returns electronically

To determine the proportion of taxpayers who prefer filing tax returns electronically, a survey of 600 taxpayers was conducted. Calculate the margin of error used to estimate this proportion. What ass...

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Q: A sample of 40 CDs from a student’s collection showed a mean

A sample of 40 CDs from a student’s collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes. Construct a 95 percent confidence interval for the population standard...

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Q: A random sample of 30 lunch orders at Noodles and Company showed

A random sample of 30 lunch orders at Noodles and Company showed a mean bill of $10.36 with a standard deviation of $5.31. Find the 95 percent confidence interval for the mean bill of all lunch orders...

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Q: The probability that a 30-year-old white male will

The probability that a 30-year-old white male will live another year is .99863. What premium would an insurance company charge to break even on a one-year $1 million term life insurance policy?

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Q: As a birthday gift, you are mailing a new personal digital

As a birthday gift, you are mailing a new personal digital assistant (PDA) to your cousin in Toledo. The PDA cost $250. There is a 2 percent chance it will be lost or damaged in the mail. Is it worth...

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Q: Discuss why you would or would not expect each of the following

Discuss why you would or would not expect each of the following variables to be normally distributed. Hint: Would you expect a single central mode and tapering tails? Would the distribution be roughly...

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Q: A sample of 20 pages was taken without replacement from a Yellow

A sample of 20 pages was taken without replacement from a Yellow Pages directory that has 1,591 pages. (a) Calculate the FPCF for this sample. (b) Should the population be considered effectively infin...

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Q: Which of the following is a continuous random variable?

Which of the following is a continuous random variable? a. Number of Honda Civics sold in a given day at a car dealership. b. Amount of gasoline used for a 200-mile trip in a Honda Civic. c. Distance...

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Q: Which of the following could be probability density functions for a continuous

Which of the following could be probability density functions for a continuous random variable? Explain. a. f (x) = .50 for 0 < x < 2 b. f (x) = 2 - x for 0 < x < 2 c. f (x) = .5x for 0 < x < 2

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Q: In a certain year, on average 10 percent of the vehicles

In a certain year, on average 10 percent of the vehicles tested for emissions failed the test. Suppose that five vehicles are tested. (a) What is the probability that all pass? (b) All but one pass? (...

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Q: Applicants for a night caretaker position are uniformly distributed in age between

Applicants for a night caretaker position are uniformly distributed in age between 25 and 65. (a) What is the mean age of an applicant? (b) The standard deviation? (c) What is the probability that an...

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Q: At Chipotle Mexican Grill, the number of calories in an order

At Chipotle Mexican Grill, the number of calories in an order of chips and salsa is normally distributed with a mean of 620 and a standard deviation of 12. Bob’s order had only 580 calories. Was this...

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Q: A plumbing supplier’s mean monthly demand for vinyl washers is 24,

A plumbing supplier’s mean monthly demand for vinyl washers is 24,212 with a standard deviation of 6,053. The mean monthly demand for steam boilers is 6.8 with a standard deviation of 1.7. Which deman...

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Q: A sample of size n = 70 showed a skewness coefficient of

A sample of size n = 70 showed a skewness coefficient of 0.773 and a kurtosis coefficient of 1.277. What is the distribution’s shape?

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Q: This year, Dolon Company’s website averaged 12,104 daily views

This year, Dolon Company’s website averaged 12,104 daily views with a standard deviation of 3,026. Last year, the mean number of daily page views was 6,804 with a standard deviation of 1,701. Describe...

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Q: The “expense ratio” is a measure of the cost of

The “expense ratio” is a measure of the cost of managing the portfolio. Investors prefer a low expense ratio, all else equal. Below are expense ratios for 23 random...

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Q: Find the standard normal area for each of the following, showing

Find the standard normal area for each of the following, showing your reasoning clearly and indicating which table you used. a. P(0 < Z < 0.50) b. P(-0.50 < Z < 0) c. P(Z > 0) d. P(Z = 0)

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Q: The table below shows average daily sales of Rice Krispies in the

The table below shows average daily sales of Rice Krispies in the month of June in 74 Noodles & Company restaurants. (a) Make a histogram for the data. (b) Would you say the distribution is skewed...

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Q: Analysis of portfolio returns over a 20-year period showed the

Analysis of portfolio returns over a 20-year period showed the statistics below. (a) Calculate and compare the coefficients of variation. (b) Why would we use a coefficient of variation? Why not just...

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Q: Analysis of annualized returns over a 10-year period showed that

Analysis of annualized returns over a 10-year period showed that prepaid tuition plans had a mean return of 6.3 percent with a standard deviation of 2.7 percent, while the Standard & Poor’s 500 stock...

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Q: Caffeine content in a 5-ounce cup of brewed coffee ranges

Caffeine content in a 5-ounce cup of brewed coffee ranges from 60 to 180 mg, depending on brew time, coffee bean type, and grind. (a) Use the midrange as a measure of center. (b) Use the Empirical Rul...

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Q: Chlorine is added to city water to kill bacteria. In a

Chlorine is added to city water to kill bacteria. In a certain year, chlorine content in water from the Lake Huron Water Treatment plant ranged from 0.79 ppm (parts per million) to 0.92 ppm. (a) Use t...

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Q: Below are monthly rents paid by 30 students who live off campus

Below are monthly rents paid by 30 students who live off campus. (a) Find the mean, median, and mode. (b) Do the measures of central tendency agree? Explain. (c) Calculate the standard deviation. (d)...

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Q: How many days in advance do travelers purchase their airline tickets?

How many days in advance do travelers purchase their airline tickets? Below are data showing the advance days for a sample of 28 passengers on United Airlines Flight 815 from Chicago to Los Angeles. (...

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Q: The durations (minutes) of 26 electric power outages in the

The durations (minutes) of 26 electric power outages in the community of Sonando Heights over the past five years are shown below. (a) Find the mean, median, and mode. (b) Are the mean and median abou...

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Q: The U.S. Postal Service will ship a Priority Mail

The U.S. Postal Service will ship a Priority Mail® Large Flat Rate Box (120 3 120 3 51⁄20) anywhere in the United States for a fixed price, regardless of weight. The weigh...

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Q: M&Ms are blended in a ratio of 13 percent brown

M&Ms are blended in a ratio of 13 percent brown, 14 percent yellow, 13 percent red, 24 percent blue, 20 percent orange, and 16 percent green. Suppose you choose a sample of two M&Ms at random from a l...

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Q: Find the standard normal area for each of the following, showing

Find the standard normal area for each of the following, showing your reasoning clearly and indicating which table you used. a. P(1.22 < Z < 2.15) b. P(-.00 < Z < 3.00) c. P(-2.00 < Z < 2.00) d. P...

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Q: (a) Use Excel functions to calculate the mean and standard

(a) Use Excel functions to calculate the mean and standard deviation for weekend occupancy rates (percent) in nine resort hotels during the off-season. (b) What conclusion would a casual observer draw...

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Q: Suppose the average time to service a Noodles & Company customer at

Suppose the average time to service a Noodles & Company customer at a certain restaurant is 3 minutes and the service time follows an exponential distribution. (a) What is the probability that a custo...

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Q: The HP dvd1040i 20X Multiformat DVD Writer has an MTBF of 70

The HP dvd1040i 20X Multiformat DVD Writer has an MTBF of 70,000 hours. (a) Assuming continuous operation, what is the probability that the DVD writer will last more than 100,000 hours? (b) Less than...

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Q: Systron Donner Inertial manufactures inertial subsystems for automotive, commercial/ industrial

Systron Donner Inertial manufactures inertial subsystems for automotive, commercial/ industrial, and aerospace and defense applications. The sensors use a one-piece, micromachined inertial sensing ele...

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Q: Automobile warranty claims for engine mount failure in a Troppo Malo 2000

Automobile warranty claims for engine mount failure in a Troppo Malo 2000 SE are rare at a certain dealership, occurring at a mean rate of 0.1 claim per month. (a) What is the probability that the dea...

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Q: At a certain clinic, 2 percent of all pap smears show

At a certain clinic, 2 percent of all pap smears show signs of abnormality. What is the expected number of pap smears that must be inspected before the first abnormal one is found?

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Q: The probability of a job offer in a given interview is .

The probability of a job offer in a given interview is .25. (a) What is the expected number of interviews until the first job offer? (b) What is the probability the first job offer occurs within the f...

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Q: The probability that a bakery customer will order a birthday cake is

The probability that a bakery customer will order a birthday cake is .04. (a) What is the expected number of customers until the first birthday cake is ordered? (b) What is the probability the first c...

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Q: In a certain city, 8 percent of the cars have a

In a certain city, 8 percent of the cars have a burned-out headlight. (a) What is the expected number that must be inspected before the first one with a burned-out headlight is found? (b) What is the...

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Q: Historically, 5 percent of a mail-order firm’s regular charge

Historically, 5 percent of a mail-order firm’s regular charge-account customers have an incorrect current address in the firm’s computer database. (a) What is the expected number of customer orders un...

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Q: In the Ardmore Hotel, 20 percent of the customers pay by

In the Ardmore Hotel, 20 percent of the customers pay by American Express credit card. (a) Of the next 10 customers, what is the probability that none pay by American Express? (b) At least two? (c) Fe...

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Q: Find the standard normal area for each of the following, showing

Find the standard normal area for each of the following, showing your reasoning clearly and indicating which table you used. a. P(-1.22 < Z < 2.15) b. P(-3.00 < Z < 2.00) c. P(Z < 2.00) d. P(Z = 0)...

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Q: For patients aged 81 to 90, the probability is .07

For patients aged 81 to 90, the probability is .07 that a coronary bypass patient will die soon after the surgery. (a) What is the expected number of operations until the first fatality? (b) What is t...

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Q: The self-reported number of hours worked per week by 204

The self-reported number of hours worked per week by 204 top executives is given below. (a) Estimate the mean, standard deviation, and coefficient of variation using an Excel worksheet to organize you...

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Q: How long does it take to fly from Denver to Atlanta on

How long does it take to fly from Denver to Atlanta on Delta Airlines? The table below shows 56 observations on flight times (in minutes) for the first week of March 2005. (a) Use the grouped data for...

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Q: A random sample of individuals who filed their own income taxes were

A random sample of individuals who filed their own income taxes were asked how much time (hours) they spent preparing last year’s federal income tax forms. (a) Estimate the mean. (b)...

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Q: This table shows the distribution of winning times in the Kentucky Derby

This table shows the distribution of winning times in the Kentucky Derby (a horse race) over 84 years. (a) From the grouped data, calculate the mean. Show your calculations clearly in a worksheet. (b)...

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Q: If we fail to reject the null hypothesis that π = .

If we fail to reject the null hypothesis that π = .50 even though the true proportion is .60, what is the probability of Type I error?

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Q: When told that over a 10-year period a mammogram test

When told that over a 10-year period a mammogram test has a false positive rate of 50 percent, Bob said, “That means that about half the women tested actually have no cancer.” Correct Bob’s mistaken i...

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Q: Suppose you always reject the null hypothesis, regardless of any sample

Suppose you always reject the null hypothesis, regardless of any sample evidence. (a) What is the probability of Type II error? (b) Why is this a bad policy?

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Q: Suppose the judge decides to acquit all defendants, regardless of the

Suppose the judge decides to acquit all defendants, regardless of the evidence. (a) What is the probability of Type I error? (b) Why is this a bad policy?

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Q: A test-preparation company advertises that its training program raises SAT

A test-preparation company advertises that its training program raises SAT scores by an average of at least 30 points. A random sample of test-takers who had completed the training showed a mean incre...

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Q: Find the standard normal area for each of the following. Sketch

Find the standard normal area for each of the following. Sketch the normal curve and shade in the area represented below. a. P(Z < -1.96) b. P(Z > 1.96) c. P(Z < 1.65) d. P(Z > -1.65)

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Q: Telemarketers use a predictive dialing system to decide whether a person actually

Telemarketers use a predictive dialing system to decide whether a person actually answers a call (as opposed to an answering machine). If so, the call is routed to a telemarketer. If no telemarketer i...

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Q: If the true mean is 50 and we reject the hypothesis that

If the true mean is 50 and we reject the hypothesis that μ = 50, what is the probability of Type II error?

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Q: Pap smears are a test for abnormal cancerous and precancerous cells taken

Pap smears are a test for abnormal cancerous and precancerous cells taken from the cervix. (a) State a pair of hypotheses and then explain the meaning of a false negative and a false positive. (b) Why...

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Q: In a commercially available fingerprint scanner (e.g., for

In a commercially available fingerprint scanner (e.g., for your home or office PC), false acceptances are 1 in 25 million, with false rejection rates of 3 percent. (a) Define Type I and II errors. (b)...

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Q: High blood pressure, if untreated, can lead to increased risk

High blood pressure, if untreated, can lead to increased risk of stroke and heart attack. A common definition of hypertension is diastolic blood pressure of 90 or more. (a) State the null and alternat...

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Q: A nuclear power plant replaces its ID card facility access system cards

A nuclear power plant replaces its ID card facility access system cards with a biometric security system that scans the iris pattern of the employee and compares it with a data bank. Users are classif...

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Q: From the display below pick five cards (without replacement) by

From the display below pick five cards (without replacement) by using random numbers. Explain your method. Why would the other sampling methods not work well in this case?

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Q: A process is normally distributed with standard deviation 12. Samples of

A process is normally distributed with standard deviation 12. Samples of size 4 are taken. Suppose that you wish to test the hypothesis that μ 5 500 at α = .05 in a left-tailed test. (a) What is the β...

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Q: A certain brand of flat white interior latex paint claims one-

A certain brand of flat white interior latex paint claims one-coat coverage of 400 square feet per gallon. The standard deviation is known to be 20. A sample of 16 gallons is tested. (a) At α = .05 in...

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Q: A poker hand (5 cards) is drawn from an ordinary

A poker hand (5 cards) is drawn from an ordinary deck of 52 cards. Find the probability of each event, showing your reasoning carefully. a. The first four cards are the four aces. b. Any four cards a...

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Q: Find the standard normal area for each of the following. Sketch

Find the standard normal area for each of the following. Sketch the normal curve and shade in the area represented below. a. P(Z < -1.28) b. P(Z > 1.28) c. P(-1.96 < Z < 1.96) d. P(-1.65 < Z < 1.6...

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Q: A certain airplane has two independent alternators to provide electrical power.

A certain airplane has two independent alternators to provide electrical power. The probability that a given alternator will fail on a one-hour flight is .02. What is the probability that (a) both wil...

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Q: Which are likely to be independent events? For those you think

Which are likely to be independent events? For those you think are not, suggest reasons why. a. Gender of two babies born consecutively in a hospital. b. Car accident rates and the driver’s gender. c...

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Q: A web server hosting company advertises 99.999 percent guaranteed network

A web server hosting company advertises 99.999 percent guaranteed network uptime. (a) How many independent network servers would be needed if each has 99 percent reliability? (b) If each has 90 percen...

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Q: The probability is 1 in 4,000,000 that a

The probability is 1 in 4,000,000 that a single auto trip in the United States will result in a fatality. Over a lifetime, an average U.S. driver takes 50,000 trips. (a) What is the probability of a f...

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Q: Four students divided the task of surveying the types of vehicles in

Four students divided the task of surveying the types of vehicles in parking lots of four different shopping malls. Each student examined 100 cars in each of four large suburban malls, resulting in th...

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Q: Refer to the contingency table shown below. (a) Calculate

Refer to the contingency table shown below. (a) Calculate each probability (i–vi) and explain in words what it means. (b) Do you see evidence that smoking and race are not independen...

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Q: Analysis of forecasters’ interest rate predictions over the period 1982–1990

Analysis of forecasters’ interest rate predictions over the period 1982–1990 was intended to see whether the predictions corresponded to what actually happened. The...

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Q: High levels of cockpit noise in an aircraft can damage the hearing

High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. Cockpit noise in a jet aircraft is mostly due to airflow at hundreds of mile...

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Q: Bob, Mary, and Jen go to dinner. Each orders

Bob, Mary, and Jen go to dinner. Each orders a different meal. The waiter forgets who ordered which meal, so he randomly places the meals before the three diners. Let C be the event that a diner gets...

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Q: If Punxsutawney Phil sees his shadow on February 2, then legend

If Punxsutawney Phil sees his shadow on February 2, then legend says that winter will last 6 more weeks. In 118 years, Phil has seen his shadow 104 times. (a) What is the probability that Phil will se...

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Q: Bob’s exam score was 2.17 standard deviations above the mean

Bob’s exam score was 2.17 standard deviations above the mean. The exam was taken by 200 students. Assuming a normal distribution, how many scores were higher than Bob’s?

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Q: On Los Angeles freeways during the rush hour, there is an

On Los Angeles freeways during the rush hour, there is an 18 percent probability that a driver is using a hand-held cell phone. Which type of probability (classical, empirical, subjective) do you thin...

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Q: Bob owns two stocks. There is an 80 percent probability that

Bob owns two stocks. There is an 80 percent probability that stock A will rise in price, while there is a 60 percent chance that stock B will rise in price. There is a 40 percent chance that both stoc...

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Q: To run its network, the Ramjac Corporation wants to install a

To run its network, the Ramjac Corporation wants to install a system with dual independent servers. Employee Bob grumbled, “But that will double the chance of system failure.” Is Bob right? Explain yo...

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Q: A study showed that trained police officers can detect a lie 65

A study showed that trained police officers can detect a lie 65 percent of the time, based on controlled studies of videotapes with real-life lies and truths. What are the odds in favor of a lie being...

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Q: The probability that a 2011 Audi A8 is stolen is .0048

The probability that a 2011 Audi A8 is stolen is .0048. Find the odds against the theft of a 2011 Audi A8. Round your answer to the nearest whole number. (www.nhtsa.gov/theft)

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Q: The probability of being struck by lightning is .00016. Find

The probability of being struck by lightning is .00016. Find the odds against being struck by lightning. Round your answer to the nearest whole number. (www.lightningsafety.noaa.gov)

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Q: Prior to the start of the 2011 NCAA Men’s Basketball playoffs,

Prior to the start of the 2011 NCAA Men’s Basketball playoffs, the reported odds that Butler University would not make it to the final game were 200 to 1. What was the implied probability that Butler...

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Q: A certain model of remote-control Stanley garage door opener has

A certain model of remote-control Stanley garage door opener has nine binary (off/on) switches. The homeowner can set any code sequence. (a) How many separate codes can be programmed? (b) If you try t...

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Q: (a) In a certain state, license plates consist of

(a) In a certain state, license plates consist of three letters (A–Z) followed by three digits (0–9). How many different plates can be issued? (b) If the state allows any six-character mix (in any ord...

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Q: An MBA program offers seven concentrations: accounting (A), finance

An MBA program offers seven concentrations: accounting (A), finance (F), human resources (H), information systems (I ), international business (B), marketing (M), and operations management (O). Studen...

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Q: Joan’s finishing time for the Bolder Boulder 10K race was 1.

Joan’s finishing time for the Bolder Boulder 10K race was 1.75 standard deviations faster than the women’s average for her age group. There were 405 women who ran in her age group. Assuming a normal d...

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Q: Two cards are drawn from an ordinary deck of 52 cards.

Two cards are drawn from an ordinary deck of 52 cards. Find the probability of each event, showing your reasoning carefully. a. Two aces. b. Two red cards. c. Two red aces. d. Two honor cards (A, K,...

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Q: There is a 30 percent chance that a bidding firm will get

There is a 30 percent chance that a bidding firm will get contract A and a 40 percent chance they will get contract B. There is a 5 percent chance that they will get both. Are the events independent?...

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Q: A couple has two children. What is the probability that both

A couple has two children. What is the probability that both are boys, given that the first is a boy?

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Q: A turboprop aircraft has two attitude gyros, driven from independent electrical

A turboprop aircraft has two attitude gyros, driven from independent electrical sources. On a six-hour flight, assume the probability of failure of each attitude gyroscope is 0.0008. Does this achieve...

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Q: In child-custody cases, about 70 percent of the fathers

In child-custody cases, about 70 percent of the fathers win the case if they contest it. In the next three custody cases, what is the probability that all three win? What assumption(s) are you making?...

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Q: Fifty-six percent of American adults eat at a table-

Fifty-six percent of American adults eat at a table-service restaurant at least once a week. Suppose that four American adults are asked if they ate at table-service restaurants last week. What is the...

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Q: If there are two riders on a city bus, what is

If there are two riders on a city bus, what is the probability that no two have the same birthday? What if there are 10 riders? 20 riders? 50 riders? Hint: Use Learning Stats from McGraw-Hill’s Connec...

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Q: For male high school athletes, a news article reported that the

For male high school athletes, a news article reported that the probability of receiving a college scholarship is .0139 for basketball players, .0324 for swimmers/divers, and .0489 for lacrosse player...

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Q: A judge concludes that there is a 20 percent chance that a

A judge concludes that there is a 20 percent chance that a certain defendant will fail to appear in court if he is released after paying a full cash bail deposit. Which type of probability (classical,...

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Q: A survey showed that 44 percent of online Internet shoppers experience some

A survey showed that 44 percent of online Internet shoppers experience some kind of technical failure at checkout (e.g., when submitting a credit card) after loading their shopping cart. Which type of...

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Q: Find the associated z-score for each of the following standard

Find the associated z-score for each of the following standard normal areas. a. Highest 10 percent b. Lowest 50 percent c. Highest 7 percent

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Q: Bob says he is 50 percent sure he could swim across the

Bob says he is 50 percent sure he could swim across the Thames River. Which type of probability (classical, empirical, subjective) do you think this is?

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Q: In the first year after its release, 83 percent of emergency

In the first year after its release, 83 percent of emergency room doctors were estimated to have tried Dermabond glue (an alternative to sutures in some situations). Which type of probability (classic...

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Q: The U.S. Cesarean section delivery rate in a recent

The U.S. Cesarean section delivery rate in a recent year was estimated at 20.6 percent. Which type of probability (classical, empirical, subjective) do you think this is?

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Q: A recent article states that there is a 2 percent chance that

A recent article states that there is a 2 percent chance that an asteroid 100 meters or more in diameter will strike the earth before 2100. Which type of probability (classical, empirical, subjective)...

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Q: On a police sergeant’s examination, the historical mean score was 80

On a police sergeant’s examination, the historical mean score was 80 with a standard deviation of 20. Four officers who were alleged to be cronies of the police chief scored 195, 171, 191, and 189, re...

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Q: The historical on-time percentage for Amtrak’s Sunset Limited is 10

The historical on-time percentage for Amtrak’s Sunset Limited is 10 percent. In July, the train was on time 0 times in 31 runs. At the .10 level of significance, has the on-time percentage fallen? Exp...

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Q: An automaker states that its cars equipped with electronic fuel injection and

An automaker states that its cars equipped with electronic fuel injection and computerized engine controls will start on the first try (hot or cold) 99 percent of the time. A survey of 100 new car own...

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Q: A quality standard says that no more than 2 percent of the

A quality standard says that no more than 2 percent of the eggs sold in a store may be cracked (not broken, just cracked). In 3 cartons (12 eggs each carton), 2 eggs are cracked. (a) At the .10 level...

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Q: An experimental medication is administered to 16 people who suffer from migraines

An experimental medication is administered to 16 people who suffer from migraines. After an hour, 10 say they feel better. Is the medication effective (i.e., is the percent who feel better greater tha...

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Q: After 7 months, none of 238 angioplasty patients who received a

After 7 months, none of 238 angioplasty patients who received a drug-coated stent to keep their arteries open had experienced restenosis (re-blocking of the arteries). (a) Use MINITAB to construct a 9...

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Q: Find the associated z-score for each of the following standard

Find the associated z-score for each of the following standard normal areas. a. Lowest 6 percent b. Highest 40 percent c. Lowest 7 percent

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Q: To protect baby scallops and ensure the survival of the species,

To protect baby scallops and ensure the survival of the species, the U.S. Fisheries and Wildlife Service requires that an average scallop must weigh at least 1/36 pound. The harbormaster at a Massachu...

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Q: A university wanted to survey alumni about their interest in lifelong learning

A university wanted to survey alumni about their interest in lifelong learning classes. They mailed questionnaires to a random sample of 600 alumni from their database of over 30,000 recent graduates....

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Q: A marketing research group wanted to collect information from existing and potential

A marketing research group wanted to collect information from existing and potential customers on the appeal of a new product. They sent out surveys to a random sample of 1,200 people from their datab...

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Q: Households can sign up for a telemarketing “no-call list

Households can sign up for a telemarketing “no-call list.” How might households who sign up differ from those who don’t? What biases might this create for telemarketers promoting (a) fi nancial planni...

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Q: (a) Make an Excel scatter plot of X 5 1990

(a) Make an Excel scatter plot of X 5 1990 assault rate per 100,000 population and Y 5 2004 assault rate per 100,000 population for the 50 U.S. states. (b) Use Excel’s =CORREL function to find the cor...

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Q: (a) Make an Excel scatter plot of X 5 airspeed

(a) Make an Excel scatter plot of X 5 airspeed (nautical miles per hour) and Y 5 cockpit noise level (decibels) for 61 aircraft flights. (b) Use Excel’s =CORREL function to find the correlation coeffi...

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Q: (a) Which of these two displays (table or graph

(a) Which of these two displays (table or graph) is more helpful in describing the salad sales by Noodles & Company? Why? (b) Write a one-sentence summary of the data. (Source: Noodles & Compa...

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Q: A study of 40 U.S. cardiac care centers showed

A study of 40 U.S. cardiac care centers showed the following ratios of nurses to beds. (a) Prepare a dot plot. (b) Prepare a frequency distribution and histogram (you may either specify the bins yours...

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Q: Download the full data set of measurements of cockpit noise level for

Download the full data set of measurements of cockpit noise level for a commercial jet airliner from the McGraw-Hill Connect® website (only six data values are shown). (a) Use Excel to make...

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Q: The first Rose Bowl (football) was played in 1902.

The first Rose Bowl (football) was played in 1902. The next was not played until 1916, but a Rose Bowl has been played every year since then. The margin of victory in each of the 95 Rose Bowls from 19...

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Q: Find the associated z-score or scores that represent the following

Find the associated z-score or scores that represent the following standard normal areas. a. Middle 50 percent b. Lowest 5 percent c. Middle 90 percent

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Q: Download the full data set from the McGraw-Hill Connect®

Download the full data set from the McGraw-Hill Connect® website (only six data values are shown). (a) Use Excel to make a scatter plot, placing GDP per Capita on the X-axis and Birth Rate...

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Q: Download the full data set of measurements of cockpit noise level for

Download the full data set of measurements of cockpit noise level for a commercial jet airliner from the McGraw-Hill Connect® website (only six data values are shown). (a) Use Excel to make...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: Download the full data set from the McGraw-Hill Connect®

Download the full data set from the McGraw-Hill Connect® website (only six data values are shown). (a) Use Excel to make a scatter plot, placing GDP per Capita on the X-axis and Birth Rate...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: Find the associated z-score or scores that represent the following

Find the associated z-score or scores that represent the following standard normal areas. a. Middle 60 percent b. Highest 2 percent c. Middle 95 percent

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare a Pareto chart of the

(a) Use Excel to prepare a Pareto chart of the following data. (b) Which three service providers account for approximately 80 percent of all responses?

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: Daily output of Marathon’s Garyville, Lousiana, refinery is normally distributed

Daily output of Marathon’s Garyville, Lousiana, refinery is normally distributed with a mean of 232,000 barrels of crude oil per day with a standard deviation of 7,000 barrels. (a) What is the probabi...

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Q: (a) What kind of display is this? (b

(a) What kind of display is this? (b) Identify its strengths and weaknesses, using the tips and checklists shown in this chapter. (c) Can you suggest any improvements? Would a different type of displa...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare an appropriate type of chart

(a) Use Excel to prepare an appropriate type of chart (bar, line, pie, scatter) to display the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effe...

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Q: (a) Use Excel to prepare a Pareto chart of the

(a) Use Excel to prepare a Pareto chart of the following data. (b) Which three service providers account for approximately 80 percent of all responses?

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Q: Insurance companies are rated by several rating agencies. The Fitch 20

Insurance companies are rated by several rating agencies. The Fitch 20-point scale is AAA, AA+, AA, AA-, A+, A, A-, BBB+, BBB, BBB-, BB+, BB, BB-, B+, B, B-, CCC+, CCC, CCC-, DD. (a) What level of mea...

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Q: A tabletop survey by a restaurant asked the question shown below.

A tabletop survey by a restaurant asked the question shown below. (a) What kind of response scale is this? (b) Suggest an alternative response scale that would be more sensitive to differences in opin...

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Q: What level of measurement (nominal, ordinal, interval, ratio

What level of measurement (nominal, ordinal, interval, ratio) is appropriate for the movie rating system that you see in TV Guide (✰, ✰✰, ✰✰✰, ✰✰✰✰)? Explain your reasoning.

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Q: Historically, 5 percent of a mail-order firm’s repeat charge

Historically, 5 percent of a mail-order firm’s repeat charge-account customers have an incorrect current address in the firm’s computer database. (a) What is the probability that none of the next 12 r...

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Q: The weight of a miniature Tootsie Roll is normally distributed with a

The weight of a miniature Tootsie Roll is normally distributed with a mean of 3.30 grams and standard deviation of 0.13 gram. (a) Within what weight range will the middle 95 percent of all miniature T...

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Q: Suggest both a Likert scale question and a response scale to measure

Suggest both a Likert scale question and a response scale to measure the following: a. A student’s rating of a particular statistics professor. b. A voter’s satisfaction with the president’s economic...

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Q: Sarpedon Corp. claims that its car batteries average at least 880

Sarpedon Corp. claims that its car batteries average at least 880 CCA (cold-cranking amps). Tests on a sample of 9 batteries yield a mean of 871 CCA with a standard deviation of 15.6 CCA. (a) State th...

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Q: Thetis Mfg. says that its outboard watercraft engine’s noise level at

Thetis Mfg. says that its outboard watercraft engine’s noise level at 75 percent throttle averages 100 decibels or less from the operator’s seating position. A random sample of 8 noise level measureme...

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Q: Malcheon Health Clinic claims that the average waiting time for a patient

Malcheon Health Clinic claims that the average waiting time for a patient is 20 minutes or less. A random sample of 15 patients shows a mean wait time of 24.77 minutes with a standard deviation of 7.2...

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Q: A web-based company has a goal of processing 95 percent

A web-based company has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are...

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Q: The average service time at a Noodles & Company restaurant was 3

The average service time at a Noodles & Company restaurant was 3.5 minutes in the previous year. Noodles implemented some time-saving measures and would like to know if they have been effective. They...

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Q: A recent study by the Government Accountability Office found that consumers got

A recent study by the Government Accountability Office found that consumers got correct answers about Medicare only 67 percent of the time when they called 1-800-MEDICARE. (a) At α = .05, would a subs...

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Q: Beer shelf life is a problem for brewers and distributors because when

Beer shelf life is a problem for brewers and distributors because when beer is stored at room temperature, its flavor deteriorates. When the average furfuryl ether content reaches 6 μg per liter, a ty...

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Q: A sample of 100 one-dollar bills from the Subway cash

A sample of 100 one-dollar bills from the Subway cash register revealed that 16 had something written on them besides the normal printing (e.g., “Bob Mary”). (a) At α = .05, is this sample evidence co...

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Q: A sample of 100 mortgages approved during the current year showed that

A sample of 100 mortgages approved during the current year showed that 31 were issued to a single-earner family or individual. The historical percentage is 25 percent. (a) At the .05 level of signific...

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Q: Which of the following could not be probability density functions for a

Which of the following could not be probability density functions for a continuous random variable? Explain. Hint: Find the area under the function f (x). a. f (x) = .25 for 0 < x < 1 b. f (x) = .25 f...

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Q: A quality control standard requires that no more than 5 percent of

A quality control standard requires that no more than 5 percent of bags of Halloween candy be underweight. A random sample of 200 bags showed that 16 were underweight. (a) At α = .025, is the standard...

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Q: Ages for the 2009 Boston Red Sox pitchers are shown below.

Ages for the 2009 Boston Red Sox pitchers are shown below. (a) Assuming this is a random sample of major league pitchers, at the 5 percent level of significance does this sample show that the true mea...

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Q: The EPA is concerned about the quality of drinking water served on

The EPA is concerned about the quality of drinking water served on airline flights. A sample of 112 flights found unacceptable bacterial contamination on 14 flights. (a) At α = .05, does this sample s...

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Q: In a major football conference, a sample showed that only 267

In a major football conference, a sample showed that only 267 out of 584 freshmen players graduated within 6 years. (a) At α = .05, does this sample contradict the claim that at least half graduate wi...

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Q: An auditor reviewed 25 oral surgery insurance claims from a particular surgical

An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard...

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Q: A digital camcorder repair service has set a goal not to exceed

A digital camcorder repair service has set a goal not to exceed an average of 5 working days from the time the unit is brought in to the time repairs are completed. A random sample of 12 repair record...

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Q: (a) A statistical study reported that a drug was effective

(a) A statistical study reported that a drug was effective with a p-value of .042. Explain in words what this tells you. (b) How would that compare to a drug that had a p-value of .087?

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Q: Bob said, “Why is a small p-value significant

Bob said, “Why is a small p-value significant, when a large one isn’t? That seems backwards.” Try to explain it to Bob, giving an example to make your point.

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Q: The sodium content of a popular sports drink is listed as 220

The sodium content of a popular sports drink is listed as 220 mg in a 32-oz bottle. Analysis of 10 bottles indicates a sample mean of 228.2 mg with a sample standard deviation of 18.2 mg. (a) Write th...

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Q: A can of peeled whole tomatoes is supposed to contain an average

A can of peeled whole tomatoes is supposed to contain an average of 19 ounces of tomatoes (excluding the juice). The actual weight is a normally distributed random variable whose standard deviation is...

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Q: The cabin of a business jet has a cabin height 5 feet

The cabin of a business jet has a cabin height 5 feet 9 inches high. If a business traveler’s height is N(5’10”, 2.7”), what percentage of the business travelers will have to stoop?

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Q: At Ajax Spring Water, a half-liter bottle of soft

At Ajax Spring Water, a half-liter bottle of soft drink is supposed to contain a mean of 520 ml. The filling process follows a normal distribution with a known process standard deviation of 4 ml. (a)...

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Q: On eight Friday quizzes, Bob received scores of 80, 85

On eight Friday quizzes, Bob received scores of 80, 85, 95, 92, 89, 84, 90, 92. He tells Prof. Hardtack that he is really a 90+ performer, but this sample just happened to fall below his true performa...

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Q: Faced with rising fax costs, a firm issued a guideline that

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below....

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Q: A U.S. dime weighs 2.268 grams when

A U.S. dime weighs 2.268 grams when minted. A random sample of 15 circulated dimes showed a mean weight of 2.256 grams with a standard deviation of .026 gram. (a) Using α = .05, is the mean weight of...

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Q: A coin was flipped 60 times and came up heads 38 times

A coin was flipped 60 times and came up heads 38 times. (a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. (b) Calculate a p-value and int...

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Q: Hammermill Premium Inkjet 24 lb. paper has a specified brightness of

Hammermill Premium Inkjet 24 lb. paper has a specified brightness of 106. (a) At α = .005, does this sample of 24 randomly chosen test sheets from a day’s production ru...

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Q: Is this sample of 25 exam scores inconsistent with the hypothesis that

Is this sample of 25 exam scores inconsistent with the hypothesis that the true variance is 64 (i.e., σ = 8)? Use the 5 percent level of significance in a two-tailed test. Show all steps, i...

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Q: The median waiting time for a liver transplant in the United States

The median waiting time for a liver transplant in the United States is 321 days. Would you expect the mean to be higher or lower than 321 days? Explain. (See http://www.livermd.org/.)

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Q: A small suburban community agreed to purchase police services from the county

A small suburban community agreed to purchase police services from the county sheriff’s department. The newspaper said, “In the past, the charge for police protection from the Sheriff’s Department has...

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Q: A company’s contractual “trigger” point for a union absenteeism penalty

A company’s contractual “trigger” point for a union absenteeism penalty is a certain distance above the mean days missed by all workers. Now the company wants to switch the trigger to a certain number...

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Q: Last year’s freshman class at Big State University totaled 5,324

Last year’s freshman class at Big State University totaled 5,324 students. Of those, 1,254 received a merit scholarship to help offset tuition costs their freshman year (although the amount varied per...

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Q: At the Midlothian Independent Bank, a study shows that the mean

At the Midlothian Independent Bank, a study shows that the mean ATM transaction takes 74 seconds, the median 63 seconds, and the mode 51 seconds. (a) Sketch the distribution, based on these statistics...

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Q: At the Eureka library, the mean time a book is checked

At the Eureka library, the mean time a book is checked out is 13 days, the median is 10 days, and the mode is 7 days. (a) Sketch the distribution, based on these statistics. (b) What factors might cau...

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Q: The median life span of a mouse is 118 weeks. (

The median life span of a mouse is 118 weeks. (a) Would you expect the mean to be higher or lower than 118? (b) Would you expect the life spans of mice to be normally distributed? Explain.

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Q: On Professor Hardtack’s last cost accounting exam, the mean score was

On Professor Hardtack’s last cost accounting exam, the mean score was 71, the median was 77, and the mode was 81. (a) Sketch the distribution, based on these statistics. (b) What factors might cause t...

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Q: A manufacturing project has five independent phases whose completion must be sequential

A manufacturing project has five independent phases whose completion must be sequential. The time to complete each phase is a random variable. The mean and standard deviation of the time for each phas...

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Q: A certain outpatient medical procedure has five steps that must be performed

A certain outpatient medical procedure has five steps that must be performed in sequence. (a) Assuming that the time (in minutes) required for each step is an independent random variable, find the mea...

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Q: Malaprop Ltd. sells two products. Daily sales of product A

Malaprop Ltd. sells two products. Daily sales of product A have a mean of $70 with a standard deviation of $10, while sales of product B have a mean of $200 with a standard deviation of $30. Sales of...

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Q: The weight of a Los Angeles Lakers basketball player averages 233.

The weight of a Los Angeles Lakers basketball player averages 233.1 pounds with a standard deviation of 34.95 pounds. To express these measurements in terms a European would understand, we could conve...

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Q: A manufacturer fills one-gallon cans (3,785 ml

A manufacturer fills one-gallon cans (3,785 ml) on an assembly line in two independent steps. First, a high-volume spigot injects most of the paint rapidly. Next, a more precise but slower spigot tops...

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Q: The Rejuvo Corp. manufactures granite countertop cleaner and polish. Quarterly

The Rejuvo Corp. manufactures granite countertop cleaner and polish. Quarterly sales Q is a random variable with a mean of 25,000 bottles and a standard deviation of 2,000 bottles. Variable cost is $8...

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Q: The time required to verify and fill a common prescription at a

The time required to verify and fill a common prescription at a neighborhood pharmacy is normally distributed with a mean of 10 minutes and a standard deviation of 3 minutes. Find the time for each ev...

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Q: In September, demand for industrial furnace boilers at a large plumbing

In September, demand for industrial furnace boilers at a large plumbing supply warehouse has a mean of 7 boilers with a standard deviation of 2 boilers. The warehouse pays a unit cost of $2,225 per bo...

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Q: The distribution of beach condominium prices in Santa Theresa ($ thousands)

The distribution of beach condominium prices in Santa Theresa ($ thousands) is T(500, 700, 2,100). (a) Find the mean. (b) Find the standard deviation. (c) Find the probability that a condo price will...

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Q: The price (dollars per 1,000 board feet) of

The price (dollars per 1,000 board feet) of Douglas fir from western Washington and Oregon varies according to a triangular distribution T(300, 350, 490). (a) Find the mean. (b) Find the standard devi...

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Q: The distribution of scores on a statistics exam is T(50

The distribution of scores on a statistics exam is T(50, 60, 95). (a) Find the mean. (b) Find the standard deviation. (c) Find the probability that a score will be less than 75. (d) Sketch the distrib...

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Q: The target population is all students in your university. You wish

The target population is all students in your university. You wish to estimate the average current Visa balance for each student. How large would the university student population have to be in order...

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Q: Suppose you want to study the number of e-mail accounts

Suppose you want to study the number of e-mail accounts owned by students in your statistics class. What kind of sample is it if you (a) survey each student who has a student ID number ending in an od...

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Q: (a) Use Excel to make a scatter plot of these

(a) Use Excel to make a scatter plot of these vehicle data, placing Weight on the X-axis and City MPG on the Y-axis. Add titles and modify the default colors, fonts, etc., as you judge appropriate to...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the following exam score data, placing Midterm on the X-axis and Final on the Y-axis. Add titles and modify the default colors, fonts, etc., as you judge approp...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data, placing Floor Space on the X-axis and Weekly Sales on the Y-axis. Add titles and modify the default colors, fonts, etc., as you judge appropriate to m...

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the lightning death data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effective. (b) Describe the pattern, if...

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Q: The time required to cook a pizza at a neighborhood pizza joint

The time required to cook a pizza at a neighborhood pizza joint is normally distributed with a mean of 12 minutes and a standard deviation of 2 minutes. Find the time for each event. Show your work....

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Q: What would be the difference in student responses to the two questions

What would be the difference in student responses to the two questions shown? Version 1: I would prefer that tuition be reduced. Version 2: Cuts in tuition are a good idea even if some classes are can...

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Q: What problems are evident in the wording of these two questions?

What problems are evident in the wording of these two questions? What is your race? What is your religious preference? ❏ White ❏ Christian ❏ Black ❏ Jewish

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the following transplant data. Modify the default colors, fonts, etc., to make the display effective. (b) Describe the pattern, if any.

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Q: (a) Use Excel to prepare a line chart to display

(a) Use Excel to prepare a line chart to display the following gasoline price data. Modify the default colors, fonts, etc., to make the display effective. (b) Change it to a 2-D column chart. Modify t...

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Q: (a) Use Excel to prepare a Pareto chart of the

(a) Use Excel to prepare a Pareto chart of the following data. (b) Which three complaint categories account for approximately 80 percent of all complaints? (c) Which category should the telephone comp...

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Q: (a) Use Excel to prepare a 2-D pie

(a) Use Excel to prepare a 2-D pie chart for the following data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effective. (b) Right-click the chart area, select...

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Q: (a) Use Excel to prepare a 2-D pie

(a) Use Excel to prepare a 2-D pie chart for these LCD (liquid crystal display) shipments data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effective. (b) Do y...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data for bottled water sales for 10 weeks, placing Price on the X-axis and Units Sold on the Y-axis. Add titles and modify the default colors, fonts, etc.,...

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Q: (a) Use Excel to make a scatter plot of these

(a) Use Excel to make a scatter plot of these vehicle data, placing Weight on the X-axis and City MPG on the Y-axis. Add titles and modify the default colors, fonts, etc., as you judge appropriate to...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the following exam score data, placing Midterm on the X-axis and Final on the Y-axis. Add titles and modify the default colors, fonts, etc., as you judge approp...

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Q: The weight of a McDonald’s cheeseburger is normally distributed with a mean

The weight of a McDonald’s cheeseburger is normally distributed with a mean of 114 ounces and a standard deviation of 7 ounces. Find the weight that corresponds to each event. Show your work. a. High...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data, placing Floor Space on the X-axis and Weekly Sales on the Y-axis. Add titles and modify the default colors, fonts, etc., as you judge appropriate to m...

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Q: An executive’s telephone log showed the lengths of 65 calls initiated during

An executive’s telephone log showed the lengths of 65 calls initiated during the last week of July. (a) Sort the data. (b) Find the mean, median, and mode. (c) Do the measures of cen...

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Q: (a) Write the Excel function for the 10 percent trimmed

(a) Write the Excel function for the 10 percent trimmed mean of a data set in cells A1:A50. (b) How many observations would be trimmed in each tail? (c) How many would be trimmed overall?

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Q: Scores on an accounting exam ranged from 42 to 96, with

Scores on an accounting exam ranged from 42 to 96, with quartiles Q1 = 61, Q2 = 77, and Q3 = 85. (a) Sketch a simple boxplot (5-number summary without fences) using a nicely scaled X-axis. (b) Descr...

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Q: In 2007, total compensation (in thousands of dollars) for

In 2007, total compensation (in thousands of dollars) for 40 randomly chosen CEOs ranged from 790 to 192,920, with quartiles Q1 = 3,825, Q2 = 8,890, and Q3 = 17,948. (a) Sketch a simple boxplot (5-num...

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Q: Waiting times (minutes) for a table at Joey’s BBQ on

Waiting times (minutes) for a table at Joey’s BBQ on Friday at 5:30 p.m. have quartiles Q1 = 21, Q2 = 27 and Q3 = 33. Using the inner fences as a criterion, would a wait time of 45 minutes be consider...

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Q: Coffee temperatures (degrees Fahrenheit) at a certain restaurant have quartiles

Coffee temperatures (degrees Fahrenheit) at a certain restaurant have quartiles Q1 = 160, Q2 = 165, and Q3 = 170. Using the inner fences as a criterion, would a temperature of 149 be considered an out...

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Q: CitiBank recorded the number of customers to use a downtown ATM during

CitiBank recorded the number of customers to use a downtown ATM during the noon hour on 32 consecutive workdays. (a) Find the mean, midrange, geometric mean, and 10 percent trimmed mean. (b) Do these...

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Q: On San Martin Boulevard, embedded sensors kept track of the vehicle

On San Martin Boulevard, embedded sensors kept track of the vehicle traffic count each hour for five weekdays, Monday through Friday between 6 a.m. and 8 p.m. (5 weeks 3 14 hours 5 70 observations). (...

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Q: On Friday night, the owner of Chez Pierre in downtown Chicago

On Friday night, the owner of Chez Pierre in downtown Chicago noted the amount spent for dinner at 28 four-person tables. (a) Find the mean, midrange, geometric mean, and 10 percent trimmed mean. (b)...

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Q: The weight of a small Starbucks coffee is a normally distributed random

The weight of a small Starbucks coffee is a normally distributed random variable with a mean of 360 grams and a standard deviation of 9 grams. Find the weight that corresponds to each event. Show your...

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Q: An executive’s telephone log showed the lengths of 65 calls initiated during

An executive’s telephone log showed the lengths of 65 calls initiated during the last week of July. (a) Find the mean, median, mode, midrange, geometric mean, and 10 percent trimmed...

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Q: The number of Internet users in Latin America grew from 78.

The number of Internet users in Latin America grew from 78.5 million in 2000 to 156.6 million in 2010. Use the geometric mean to find the annual growth rate.

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Q: Your laptop gets warm (even hot) when you place it

Your laptop gets warm (even hot) when you place it on your lap because it is dissipating heat from its microprocessor and related components. (a) Use the information in the following table to make a s...

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Q: In fuel economy tests in city driving conditions, a hybrid vehicle’s

In fuel economy tests in city driving conditions, a hybrid vehicle’s mean was 43.2 mpg with a standard deviation of 2.2 mpg. A comparably sized gasoline vehicle’s mean was 27.2 mpg with a standard dev...

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Q: (a) Make a scatter plot of the following data on

(a) Make a scatter plot of the following data on X 5 home size and Y 5 selling price (thousands of dollars) for new homes (n 5 20) in a suburb of an eastern city. (b) Find the sample correlation coeff...

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Q: Over the past month, Bob’s bowling score mean was 182 with

Over the past month, Bob’s bowling score mean was 182 with a standard deviation of 9.1. His bowling partner Cedric’s mean was 152 with a standard deviation of 7.6. Which bowler is more consistent in r...

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Q: Use Excel’s AVEDEV function to find the mean absolute deviation (MAD

Use Excel’s AVEDEV function to find the mean absolute deviation (MAD) of the integers 1 through 10.

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Q: Use Excel’s AVEDEV function to find the mean absolute deviation (MAD

Use Excel’s AVEDEV function to find the mean absolute deviation (MAD) of these five numbers: 12, 18, 21, 22, 27.

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Q: Noodles and Company tested consumer reaction to two spaghetti sauces. Each

Noodles and Company tested consumer reaction to two spaghetti sauces. Each of 70 raters assessed both sauces on a scale of 1 (worst) to 10 (best) using several taste criteria. To correct for possible...

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Q: (a) By Chebyshev’s Theorem, at least how many students

(a) By Chebyshev’s Theorem, at least how many students in a class of 200 would score within the range μ 6 2σ? (b) By the Empirical Rule, how many students in a class of 200 would score within the rang...

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Q: The weights of newborn babies in Foxboro Hospital are normally distributed with

The weights of newborn babies in Foxboro Hospital are normally distributed with a mean of 6.9 pounds and a standard deviation of 1.2 pounds. (a) How unusual is a baby weighing 8.0 pounds or more? (b)...

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Q: An exam has a mean of 70 with a standard deviation of

An exam has a mean of 70 with a standard deviation of 10. Use Chebyshev’s Theorem to find a lower bound for the number of students in a class of 400 who scored between 50 and 90.

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Q: A credit card customer at Barnes and Noble can use Visa (

A credit card customer at Barnes and Noble can use Visa (V), MasterCard (M), or American Express (A). The merchandise may be books (B), electronic media (E), or other (O). (a) Enumerate the elementary...

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Q: Based on the reported experience of climbers from a given year,

Based on the reported experience of climbers from a given year, a climber who attempts Everest has a 31 percent chance of success.

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Q: An entrepreneur who plans to open a Cuban restaurant in Nashville has

An entrepreneur who plans to open a Cuban restaurant in Nashville has a 20 percent chance of success.

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Q: Given P(A) = .40, P(B

Given P(A) = .40, P(B) = .50, and P(A ∩ B) = .05, find (a) P(A ∪ B), (b) P(A | B), and (c) P(B | A).

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Q: Given P(A) = .70, P(B

Given P(A) = .70, P(B) = .30, and P(A ∩ B) = .00, find (a) P(A ∪ B), (b) P(A | B), and (c) P(B | A).

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Q: Suppose Samsung ships 21.7 percent of the liquid crystal displays

Suppose Samsung ships 21.7 percent of the liquid crystal displays (LCDs) in the world. Let S be the event that a randomly selected LCD was made by Samsung. Find (a) P(S), (b) P(S’), (c) the odds in fa...

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Q: Suppose the probability of an IRS audit is 1.7 percent

Suppose the probability of an IRS audit is 1.7 percent for U.S. taxpayers who file form 1040 and who earned $100,000 or more. (a) What are the odds that such a taxpayer will be audited? (b) What are t...

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Q: List two mutually exclusive events that describe the possible outcomes of each

List two mutually exclusive events that describe the possible outcomes of each situation. a. A pharmaceutical firm seeks FDA approval for a new drug. b. A baseball batter goes to bat. c. A woman has a...

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Q: A survey asked tax accounting firms their business form (S 5

A survey asked tax accounting firms their business form (S 5 sole proprietorship, P 5 partnership, C 5 corporation) and type of risk insurance they carry (L 5 liability only, T 5 property loss only, B...

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Q: The credit scores of 35-year-olds applying for a

The credit scores of 35-year-olds applying for a mortgage at Ulysses Mortgage Associates are normally distributed with a mean of 600 and a standard deviation of 100. (a) Find the credit score that def...

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Q: List more than two events (i.e., categorical events

List more than two events (i.e., categorical events) that might describe the outcome of each situation. a. A student applies for admission to Oxnard University. b. A football quarterback throws a pass...

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Q: Given P(J) = .26, P(K

Given P(J) = .26, P(K) = .48. If A and B are independent, find P(J ∪ K).

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Q: Given P(A) = .40, P(B

Given P(A) = .40, P(B) = .50. If A and B are independent, find P(A ∩ B).

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Q: Given P(A) = .40, P(B

Given P(A) = .40, P(B) = .50, and P(A ∩ B) = .05. (a) Find P(A | B). (b) In this problem, are A and B independent?

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Q: The probability that a student has a Visa card (event V

The probability that a student has a Visa card (event V) is .73. The probability that a student has a MasterCard (event M) is .18. The probability that a student has both cards is .03. (a) Find the pr...

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Q: A baseball player bats either left-handed (L) or

A baseball player bats either left-handed (L) or right-handed (R). The player either gets on base (B) or does not get on base (B9). (a) Enumerate the elementary events in the sample space. (b) Would t...

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Q: A hospital’s backup power system has three independent emergency electrical generators,

A hospital’s backup power system has three independent emergency electrical generators, each with uptime averaging 95 percent (some downtime is necessary for maintenance). Any of the generators can ha...

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Q: Suppose 50 percent of the customers at Pizza Palooza order a square

Suppose 50 percent of the customers at Pizza Palooza order a square pizza, 80 percent order a soft drink, and 40 percent order both a square pizza and a soft drink. Is ordering a soft drink independen...

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Q: The contingency table below summarizes a survey of 1,000 bottled

The contingency table below summarizes a survey of 1,000 bottled beverage consumers. Find the following probabilities or percentages: a. Probability that a consumer recycles beverage bottles. b. Prob...

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Q: Based on the previous problem, is major independent of gender?

Based on the previous problem, is major independent of gender? Explain the basis for your conclusion.

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Q: At a Noodles & Company restaurant, the probability that a customer

At a Noodles & Company restaurant, the probability that a customer will order a nonalcoholic beverage is .38. Use Excel to find the probability that in a sample of 5 customers (a) none of the 5 will o...

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Q: For a continuous PDF, why can’t we sum the probabilities of

For a continuous PDF, why can’t we sum the probabilities of all x-values to get the total area under the curve?

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Q: A die is thrown (1, 2, 3, 4

A die is thrown (1, 2, 3, 4, 5, 6) and a coin is tossed (H, T). (a) Enumerate the elementary events in the sample space for the die/coin combination. (b) Are the elementary events equally likely? Expl...

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Q: Of grocery shoppers who have a shopping cart, 70 percent pay

Of grocery shoppers who have a shopping cart, 70 percent pay by credit/debit card (event C1), 20 percent pay cash (event C2), and 10 percent pay by check (event C3). Of shoppers without a grocery cart...

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Q: A study showed that 60 percent of The Wall Street Journal subscribers

A study showed that 60 percent of The Wall Street Journal subscribers watch CNBC every day. Of these, 70 percent watch it outside the home. Only 20 percent of those who don’t watch CNBC every day watc...

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Q: Half of a set of the parts are manufactured by machine A

Half of a set of the parts are manufactured by machine A and half by machine B. Four percent of all the parts are defective. Six percent of the parts manufactured on machine A are defective. Find the...

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Q: (a) Find 8! without a calculator. Show your

(a) Find 8! without a calculator. Show your work. (b) Use your calculator to find 32!. (c) Find 32! by typing “32!” in the Google search window. (d) Which method would you use most often? Why?

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Q: (a) Find 20C5 without a calculator. Show your work

(a) Find 20C5 without a calculator. Show your work. (b) Use your calculator to find 20C5. (c) Find 20C5 by entering “20 choose 5” in the Google search window. (d) Which method would you use most often...

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Q: American Express Business Travel uses a six-letter record locator number

American Express Business Travel uses a six-letter record locator number (RLN) for each client’s trip (e.g., KEZLFS). (a) How many different RLNs can be created using capital letters (A–Z)? (b) What i...

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Q: “There is a 20% chance that a new stock offered

“There is a 20% chance that a new stock offered in an initial public offering (IPO) will reach or exceed its target price on the first day.”

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Q: Until 2005, the UPC bar code had 12 digits (0

Until 2005, the UPC bar code had 12 digits (0–9). The first six digits represent the manufacturer, the next five represent the product, and the last is a check digit. (a) How many different manufactur...

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Q: Bob has to study for four final exams: accounting (A

Bob has to study for four final exams: accounting (A), biology (B), communications (C), and drama (D). (a) If he studies one subject at a time, in how many different ways could he arrange them? (b) Li...

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Q: Vail Resorts pays part-time seasonal employees at ski resorts on

Vail Resorts pays part-time seasonal employees at ski resorts on an hourly basis. At a certain mountain, the hourly rates have a normal distribution with σ 5 $3.00. If 20 percent of all part time seas...

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Q: (a) In how many ways could you arrange seven books

(a) In how many ways could you arrange seven books on a shelf? (b) Would it be feasible to list the possible arrangements?

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Q: Find the following permutations nPr: a. n =

Find the following permutations nPr: a. n = 8 and r = 3. b. n = 8 and r = 5. c. n = 8 and r = 1. d. n = 8 and r = 8.

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Q: Find the following combinations nCr: a. n =

Find the following combinations nCr: a. n = 8 and r = 3. b. n = 8 and r = 5. c. n = 8 and r = 1. d. n = 8 and r = 8.

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Q: “There is a 25% chance that AT&T Wireless

“There is a 25% chance that AT&T Wireless and Verizon will merge.”

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Q: “Commercial rocket launches have a 95% success rate.”

“Commercial rocket launches have a 95% success rate.”

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Q: “The probability of rolling three sevens in a row with dice

“The probability of rolling three sevens in a row with dice is .0046.”

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Q: Which of the following could not be probability distributions? Explain.

Which of the following could not be probability distributions? Explain.

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Q: Find the mean and standard deviation of four-digit uniformly distributed

Find the mean and standard deviation of four-digit uniformly distributed lottery numbers (0000 through 9999).

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Q: The ages of Java programmers at SynFlex Corp. range from 20

The ages of Java programmers at SynFlex Corp. range from 20 to 60. (a) If their ages are uniformly distributed, what would be the mean and standard deviation? (b) What is the probability that a random...

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Q: List the X values that are included in each italicized event.

List the X values that are included in each italicized event. a. You can miss at most 2 quizzes out of 16 quizzes (X = number of missed quizzes). b. You go to Starbuck’s at least 4 days a week (X = n...

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Q: Use Excel to find each probability. a. P

Use Excel to find each probability. a. P(80 < X < 110) for N(100, 15) b. P(1.50 < X < 2.00) for N(0, 1) c. P(4,500 < X < 7,000) for N(6000, 1000) d. P(225 < X < 450) for N(600, 100)

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Q: Write the probability of each italicized event in symbols (e.

Write the probability of each italicized event in symbols (e.g., P(X > 5). a. At least 7 correct answers on a 10-question quiz (X = number of correct answers). b. Fewer than 4 “phishing” e-mails out...

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Q: Find the mean and standard deviation for each binomial random variable:

Find the mean and standard deviation for each binomial random variable: a. n = 8, π = .10 b. n = 10, π = .40 c. n = 12, π = .50

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Q: Find the mean and standard deviation for each binomial random variable:

Find the mean and standard deviation for each binomial random variable: a. n = 30, π = .90 b. n = 80, π = .70 c. n = 20, π = .80

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Q: Calculate each binomial probability: a. X = 5

Calculate each binomial probability: a. X = 5, n = 9, π = .90 b. X = 0, n = 6, π = .20 c. X = 9, n = 9, π = .80

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Q: Calculate each binomial probability: a. X = 2

Calculate each binomial probability: a. X = 2, n = 8, π = .10 b. X = 1, n = 10, π = .40 c. X = 3, n = 12, π = .70

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Q: Calculate each compound event probability: a. X <

Calculate each compound event probability: a. X < 3, n = 8, π = .20 b. X > 7, n = 10, π = .50 c. X < 3, n = 6, π = .70

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Q: Calculate each compound event probability: a. X <

Calculate each compound event probability: a. X < 10, n = 14, π = .95 b. X > 2, n = 5, π = .45 c. X < 1, n = 10, π = .15

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Q: Calculate each binomial probability: a. More than 10

Calculate each binomial probability: a. More than 10 successes in 16 trials with an 80 percent chance of success. b. At least 4 successes in 8 trials with a 40 percent chance of success. c. No more t...

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Q: Calculate each binomial probability: a. Fewer than 4

Calculate each binomial probability: a. Fewer than 4 successes in 12 trials with a 10 percent chance of success. b. At least 3 successes in 7 trials with a 40 percent chance of success. c. At most 9...

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Q: Find the mean and standard deviation for each Poisson:

Find the mean and standard deviation for each Poisson: a. λ = 1.0 b. λ = 2.0 c. λ = 4.0

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Q: The weight of a small Starbucks coffee is a normal random variable

The weight of a small Starbucks coffee is a normal random variable with a mean of 360 g and a standard deviation of 9 g. Use Excel to find the weight corresponding to each percentile of weight. a. 10...

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Q: Find the mean and standard deviation for each Poisson: a

Find the mean and standard deviation for each Poisson: a. λ = 9.0 b. λ = 12.0 c. λ = 7.0

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Q: Calculate each Poisson probability: a. P(X =

Calculate each Poisson probability: a. P(X = 6), λ = 4.0 b. P(X = 10), λ = 12.0 c. P(X = 4), λ = 7.0

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Q: Calculate each Poisson probability: a. P(X

Calculate each Poisson probability: a. P(X = 2), λ = 0.1 b. P(X = 1), λ = 2.2 c. P(X = 3), λ = 1.6

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Q: Calculate each compound event probability: a. P(

Calculate each compound event probability: a. P(X < 3), λ = 4.3 b. P(X > 7), λ = 5.2 c. P(X < 3), λ = 2.7

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Q: The average number of items (such as a drink or dessert

The average number of items (such as a drink or dessert) ordered by a Noodles & Company customer in addition to the meal is 1.4. These items are called add-ons. Define X to be the number of add-ons or...

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Q: (a) Why might the number of yawns per minute by

(a) Why might the number of yawns per minute by students in a warm classroom not be a Poisson event? (b) Give two additional examples of events per unit of time that might violate the assumptions of t...

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Q: An experienced order taker at the L.L. Bean call

An experienced order taker at the L.L. Bean call center has a .003 chance of error on each keystroke (i.e., π = .003). In 500 keystrokes, find the approximate probability of (a) at least two errors an...

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Q: The probability of a manufacturing defect in an aluminum beverage can is

The probability of a manufacturing defect in an aluminum beverage can is .00002. If 100,000 cans are produced, find the approximate probability of (a) at least one defective can and (b) two or more de...

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Q: In a string of 100 Christmas lights, there is a .

In a string of 100 Christmas lights, there is a .01 chance that a given bulb will fail within the first year of use (if one bulb fails, it does not affect the others). Find the approximate probability...

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Q: The probability that a passenger’s bag will be mishandled on a U

The probability that a passenger’s bag will be mishandled on a U.S. airline is .0046. During spring break, suppose that 500 students fly from Minnesota to various southern destinations. (a) What is th...

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Q: The default rate on government-guaranteed student loans at a certain

The default rate on government-guaranteed student loans at a certain public four-year institution is 7 percent. (a) If 1,000 student loans are made, what is the probability of fewer than 50 defaults?...

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Q: ABC Warehouse has eight refrigerators in stock. Two are side-

ABC Warehouse has eight refrigerators in stock. Two are side-by-side models and six are top freezer models. (a) Using Excel, calculate the entire hypergeometric probability distribution for the number...

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Q: Find each geometric probability. a. P(X

Find each geometric probability. a. P(X = 5) when π = .50 b. P(X = 3) when π = .25 c. P(X = 4) when π = .60

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Q: In the Ardmore Hotel, 20 percent of the guests (the

In the Ardmore Hotel, 20 percent of the guests (the historical percentage) pay by American Express credit card. (a) What is the expected number of guests until the next one pays by American Express cr...

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Q: In a certain Kentucky Fried Chicken franchise, half of the customer’s

In a certain Kentucky Fried Chicken franchise, half of the customer’s request “crispy” instead of “original,” on average. (a) What is the expected number of customers before the next customer requests...

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Q: The height of a Los Angeles Lakers basketball player averages 6 feet

The height of a Los Angeles Lakers basketball player averages 6 feet 7.6 inches (i.e., 79.6 inches) with a standard deviation of 3.24 inches. To convert from inches to centimeters, we multiply by 2.54...

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Q: Pepsi and Mountain Dew products sponsored a contest giving away a Lamborghini

Pepsi and Mountain Dew products sponsored a contest giving away a Lamborghini sports car worth $215,000. The probability of winning from a single bottle purchase was .00000884. Find the expected value...

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Q: The mean January temperature in Fort Collins, CO, is 37

The mean January temperature in Fort Collins, CO, is 37.18 F with a standard deviation of 10.38 F. Express these Fahrenheit parameters in degrees Celsius using the transformation C = 5y9F - 17.78.

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Q: There are five accounting exams. Bob’s typical score on each exam

There are five accounting exams. Bob’s typical score on each exam is a random variable with a mean of 80 and a standard deviation of 5. His final grade is based on the sum of his exam scores. (a) Find...

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Q: Student Life Insurance Company wants to offer an insurance plan with a

Student Life Insurance Company wants to offer an insurance plan with a maximum claim amount of $5,000 for dorm students to cover theft of certain items. Past experience suggests that the probability o...

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Q: A lottery ticket has a grand prize of $28 million.

A lottery ticket has a grand prize of $28 million. The probability of winning the grand prize is .000000023. Based on the expected value of the lottery ticket, would you pay $1 for a ticket? Show your...

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Q: In a certain store, there is a .03 probability that

In a certain store, there is a .03 probability that the scanned price in the bar code scanner will not match the advertised price. The cashier scans 800 items. (a) What is the expected number of misma...

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Q: Oxnard Petro Ltd. is buying hurricane insurance for its off-

Oxnard Petro Ltd. is buying hurricane insurance for its off-coast oil drilling platform. During the next five years, the probability of total loss of only the above-water superstructure ($250 million)...

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Q: Flight 202 is departing Los Angeles. Is each random variable discrete

Flight 202 is departing Los Angeles. Is each random variable discrete (D) or continuous (C)? a. Number of airline passengers traveling with children under age 3. b. Proportion of passengers traveling...

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Q: (a) At what x value does f (x)

(a) At what x value does f (x) reach a maximum for a normal distribution N(75, 5)? (b) Does f (x) touch the X-axis at μ ± 3σ?

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Q: State the Empirical Rule for a normal distribution.

State the Empirical Rule for a normal distribution.

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Q: It is Saturday morning at Starbucks. Is each random variable discrete

It is Saturday morning at Starbucks. Is each random variable discrete (D) or continuous (C)? a. Temperature of the coffee served to a randomly chosen customer. b. Number of customers who order only c...

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Q: High school students across the nation compete in a financial capability challenge

High school students across the nation compete in a financial capability challenge each year by taking a National Financial Capability Challenge Exam. Students who score in the top 20 percent are reco...

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Q: The fastest 10 percent of runners who complete the Nosy Neighbor 5K

The fastest 10 percent of runners who complete the Nosy Neighbor 5K race win a gift certificate to a local running store. Assuming a normal distribution, how many standard deviations below the mean mu...

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Q: Assume that the number of calories in a McDonald’s Egg McMuffin is

Assume that the number of calories in a McDonald’s Egg McMuffin is a normally distributed random variable with a mean of 290 calories and a standard deviation of 14 calories. (a) What is the probabili...

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Q: The pediatrics unit at Carver Hospital has 24 beds. The number

The pediatrics unit at Carver Hospital has 24 beds. The number of patients needing a bed at any point in time is N(19.2, 2.5). What is the probability that the number of patients needing a bed will ex...

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Q: On January 1, 2011, a new standard for baseball bat

On January 1, 2011, a new standard for baseball bat “liveliness” called BBCOR (Ball-Bat Coefficient of Restitution) was adopted for teams playing under NCAA rules. A higher BBCOR allows the ball to tr...

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Q: The probability is .90 that a vending machine in the Oxnard

The probability is .90 that a vending machine in the Oxnard University Student Center will dispense the desired item when correct change is inserted. If 200 customers try the machine, find the probabi...

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Q: The number of patients needing a bed at any point in time

The number of patients needing a bed at any point in time in the pediatrics unit at Carver Hospital is N(19.2, 2.5). Find the middle 50 percent of the number of beds needed (round to the next higher i...

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Q: The average cost of an IRS Form 1040 tax filing at Thetis

The average cost of an IRS Form 1040 tax filing at Thetis Tax Service is $157.00. Assuming a normal distribution, if 70 percent of the filings cost less than $171.00, what is the standard deviation?

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Q: Use Excel to find each probability. a. P

Use Excel to find each probability. a. P(X < 110) for N(100, 15) b. P(X < 2.00) for N(0, 1) c. P(X < 5,000) for N(6000, 1000) d. P(X < 450) for N(600, 100)

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Q: A study found that the mean waiting time to see a physician

A study found that the mean waiting time to see a physician at an outpatient clinic was 40 minutes with a standard deviation of 28 minutes. Use Excel to find each probability. (a) What is the probabil...

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Q: High-strength concrete is supposed to have a compressive strength greater

High-strength concrete is supposed to have a compressive strength greater than 6,000 pounds per square inch (psi). A certain type of concrete has a mean compressive strength of 7,000 psi, but due to v...

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Q: Find the mean and standard deviation for each uniform continuous model.

Find the mean and standard deviation for each uniform continuous model. a. U (0, 10) b. U (100, 200) c. U (1, 99)

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Q: In Santa Theresa, false alarms are received at the downtown fire

In Santa Theresa, false alarms are received at the downtown fire station at a mean rate of 0.3 per day. (a) What is the probability that more than 7 days will pass before the next false alarm arrives?...

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Q: A passenger metal detector at Chicago’s Midway Airport gives an alarm 2

A passenger metal detector at Chicago’s Midway Airport gives an alarm 2.1 times a minute. What is the probability that (a) less than 60 seconds will pass before the next alarm? (b) More than 30 second...

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Q: The Johnson family uses a propane gas grill for cooking outdoors.

The Johnson family uses a propane gas grill for cooking outdoors. During the summer they need to replace their tank on average every 30 days. At a randomly chosen moment, what is the probability that...

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Q: Suppose that the distribution of order sizes (in dollars) at

Suppose that the distribution of order sizes (in dollars) at L.L. Bean has a distribution that is T(0, 25, 75). (a) Find the mean. (b) Find the standard deviation. (c) Find the probability that an ord...

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Q: When confronted with an in-flight medical emergency, pilots and

When confronted with an in-flight medical emergency, pilots and crew can consult staff physicians at a global response center located in Arizona. If the global response center is called, there is a 4....

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Q: Suppose that the distribution of oil prices ($/bbl) is forecast

Suppose that the distribution of oil prices ($/bbl) is forecast to be T(50, 65, 105). (a) Find the mean. (b) Find the standard deviation. (c) Find the probability that the price will be greater than $...

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Q: For a continuous uniform distribution, why is P(25 <

For a continuous uniform distribution, why is P(25 < X < 45) the same as P(25 < X < 45)?

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Q: Assume the weight of a randomly chosen American passenger car is a

Assume the weight of a randomly chosen American passenger car is a uniformly distributed random variable ranging from 2,500 pounds to 4,500 pounds. (a) What is the mean weight of a randomly chosen veh...

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Q: If all normal distributions have the same shape, how do they

If all normal distributions have the same shape, how do they differ?

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Q: Construct a confidence interval for μ assuming that each sample is from

Construct a confidence interval for μ assuming that each sample is from a normal population. a. x bar = 24, σ = 3, n = 10, 90 percent confidence b. x bar = 125, σ = 8, n = 25, 99 percent confidence c....

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Q: Use the sample information x bar = 37, σ = 5

Use the sample information x bar = 37, σ = 5, n = 15 to calculate the following confidence intervals for μ assuming the sample is from a normal population: (a) 90 percent confidence; (b) 95 percent co...

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Q: A random sample of 25 items is drawn from a population whose

A random sample of 25 items is drawn from a population whose standard deviation is known to be σ = 40. The sample mean is x bar = 270. a. Construct an interval estimate for μ with 95 percent confidenc...

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Q: A random sample of 100 items is drawn from a population whose

A random sample of 100 items is drawn from a population whose standard deviation is known to be σ = 50. The sample mean is x bar = 850. a. Construct an interval estimate for μ with 95 percent confiden...

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Q: The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder

The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder 3.5 L automatic 5-speed using premium fuel is normally distributed with a known standard deviation of 1.25 MPG. If a random sample of 10 tanks of...

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Q: Guest ages at a Vail Resorts ski mountain typically have a right

Guest ages at a Vail Resorts ski mountain typically have a right-skewed distribution. Assume the standard deviation (σ) of age is 14.5 years. (a) Even though the population distribution of age is righ...

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Q: On average, 28 patients per hour arrive in the Foxboro 24

On average, 28 patients per hour arrive in the Foxboro 24-Hour Walk-in Clinic on Friday between 6 p.m. and midnight. (a) What is the approximate probability of more than 35 arrivals? (b) What is the a...

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Q: The Ball Corporation’s beverage can manufacturing plant in Fort Atkinson, Wisconsin

The Ball Corporation’s beverage can manufacturing plant in Fort Atkinson, Wisconsin, uses a metal supplier that provides metal with a known thickness standard deviation σ = .000959 mm. If a random sam...

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Q: Find a confidence interval for μ assuming that each sample is from

Find a confidence interval for μ assuming that each sample is from a normal population. a. x bar = 24, s = 3, n = 7, 90 percent confidence b. x bar = 42, s = 6, n = 18, 99 percent confidence c. x bar...

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Q: For each value of d.f. (degrees of freedom

For each value of d.f. (degrees of freedom), look up the value of Student’s t in Appendix D for the stated level of confidence. Then use Excel to find the value of Student’s t to four decimal places....

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Q: Find the interval within which 95 percent of the sample

Find the interval within which 95 percent of the sample means would be expected to fall, assuming that each sample is from a normal population. a. μ = 200, σ = 12, n = 36 b. μ = 1,000, σ = 15, n =...

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Q: A sample of 21 minivan electrical warranty repairs for “loose,

A sample of 21 minivan electrical warranty repairs for “loose, not attached” wires (one of several electrical failure categories the dealership mechanic can select) showed a mean repair cost of $45.66...

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Q: A random sample of monthly rent paid by 12 college seniors living

A random sample of monthly rent paid by 12 college seniors living off campus gave the results below (in dollars). Find a 99 percent confidence interval for μ, assuming that the sample is...

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Q: A random sample of 10 shipments of stick-on labels showed

A random sample of 10 shipments of stick-on labels showed the following order sizes. (a) Construct a 95 percent confidence interval for the true mean order size. (b) How could the confidence interval...

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Q: Calculate the standard error of the sample proportion. a

Calculate the standard error of the sample proportion. a. n = 30, π = .50 b. n = 50, π = .20 c. n = 100, π = .10 d. n = 500, π = .005

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Q: Calculate the standard error of the sample proportion. a.

Calculate the standard error of the sample proportion. a. n = 40, π = .30 b. n = 200, π = .10 c. n = 30, π = .40 d. n = 400, π = .03

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Q: Should p be assumed normal? a. n = 200

Should p be assumed normal? a. n = 200, π = .02 b. n = 100, π = .05 c. n = 50, π = .50

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Q: For a large Internet service provider (ISP), web virus attacks

For a large Internet service provider (ISP), web virus attacks occur at a mean rate of 150 per day. (a) Estimate the probability of at least 175 attacks in a given day. (b) Estimate the probability of...

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Q: Should p be assumed normal? a. n = 25

Should p be assumed normal? a. n = 25, π = .50 b. n = 60, π = .20 c. n = 100, π = .08

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Q: Find the margin of error for a poll, assuming that π

Find the margin of error for a poll, assuming that π = .50. a. n = 50 b. n = 200 c. n = 500 d. n = 2,000

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Q: A car dealer is taking a customer satisfaction survey. Find the

A car dealer is taking a customer satisfaction survey. Find the margin of error (i.e., assuming 95% confidence and π = .50) for (a) 250 respondents, (b) 125 respondents, and (c) 65 respondents.

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Q: In a sample of 500 new websites registered on the Internet,

In a sample of 500 new websites registered on the Internet, 24 were anonymous (i.e., they shielded their name and contact information). (a) Construct a 95 percent confidence interval for the proportio...

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Q: From a list of stock mutual funds, 52 funds were selected

From a list of stock mutual funds, 52 funds were selected at random. Of the funds chosen, it was found that 19 required a minimum initial investment under $1,000. (a) Construct a 90 percent confidence...

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Q: Of 43 bank customers depositing a check, 18 received some cash

Of 43 bank customers depositing a check, 18 received some cash back. (a) Construct a 90 percent confidence interval for the proportion of all depositors who ask for cash back. (b) Check the normality...

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Q: A survey showed that 4.8 percent of the 250 Americans

A survey showed that 4.8 percent of the 250 Americans surveyed had suffered some kind of identity theft in the past 12 months. (a) Construct a 99 percent confidence interval for the true proportion of...

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Q: A random survey of 500 students was conducted from a population of

A random survey of 500 students was conducted from a population of 2,300 students to estimate the proportion who had part-time jobs. The sample showed that 245 had part-time jobs. Calculate the 90 per...

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Q: Last year, a study showed that the average ATM cash withdrawal

Last year, a study showed that the average ATM cash withdrawal took 65 seconds with a standard deviation of 10 seconds. The study is to be repeated this year. How large a sample would be needed to est...

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Q: Popcorn kernels are believed to take between 100 and 200 seconds to

Popcorn kernels are believed to take between 100 and 200 seconds to pop in a certain microwave. (a) Estimate σ using Method 3 from Table 8.11. (b) What sample size (number of kernels) would...

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Q: J.D. Power and Associates says that 60 percent of

J.D. Power and Associates says that 60 percent of car buyers now use the Internet for research and price comparisons. (a) Find the probability that in a sample of 8 car buyers, all 8 will use the Inte...

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Q: Between 11 p.m. and midnight on Thursday night,

Between 11 p.m. and midnight on Thursday night, Mystery Pizza gets an average of 4.2 telephone orders per hour. Find the probability that (a) at least 30 minutes will elapse before the next telephone...

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Q: Analysis showed that the mean arrival rate for vehicles at a certain

Analysis showed that the mean arrival rate for vehicles at a certain Shell station on Friday afternoon last year was 4.5 vehicles per minute. How large a sample would be needed to estimate this year’s...

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Q: Noodles & Company wants to estimate the mean spending per customer at

Noodles & Company wants to estimate the mean spending per customer at a certain restaurant with 95 percent confidence and an error of ±$0.25. What is the required sample size, assuming a standard devi...

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Q: In an intra-squad swim competition, men’s freestyle 100 swim

In an intra-squad swim competition, men’s freestyle 100 swim times at a certain university ranged from 43.89 seconds to 51.96 seconds. (a) Estimate the standard deviation using Method 3 (the Empirical...

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Q: The city fuel economy of a 2009 Toyota 4Runner 2WD 6 cylinder

The city fuel economy of a 2009 Toyota 4Runner 2WD 6 cylinder 4 L automatic 5-speed using regular gas is a normally distributed random variable with a range 16 MPG to 21 MPG. (a) Estimate the standard...

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Q: (a) Find the standard error of the mean for each

(a) Find the standard error of the mean for each sampling situation (assuming a normal population). (b) What happens to the standard error each time you quadruple the sample size? a. σ = 32, n = 4 b....

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Q: What sample size would be needed to estimate the true proportion of

What sample size would be needed to estimate the true proportion of American households that own more than one DVD player, with 90 percent confidence and an error of ±0.02?

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Q: What sample size would be needed to estimate the true proportion of

What sample size would be needed to estimate the true proportion of American adults who know their cholesterol level, using 95 percent confidence and an error of ±0.02?

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Q: Inspection of a random sample of 19 aircraft showed that 15 needed

Inspection of a random sample of 19 aircraft showed that 15 needed repairs to fix a wiring problem that might compromise safety. How large a sample would be needed to estimate the true proportion of j...

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Q: Find the 95 percent confidence interval for the population variance from these

Find the 95 percent confidence interval for the population variance from these samples. a. n = 15 commuters, s = 10 miles driven b. n = 18 students, s = 12 study hours

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Q: The weights of 20 oranges (in ounces) are shown below

The weights of 20 oranges (in ounces) are shown below. Construct a 95 percent confidence interval for the population standard deviation. Note: Scale was only accurate to the nearest ¼ ou...

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Q: At a certain Noodles & Company restaurant, customers arrive during the

At a certain Noodles & Company restaurant, customers arrive during the lunch hour at a rate of 2.8 per minute. What is the probability that (a) at least 30 seconds will pass before the net customer wa...

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Q: A pediatrician’s records showed the mean height of a random sample of

A pediatrician’s records showed the mean height of a random sample of 25 girls at age 12 months to be 29.530 inches with a standard deviation of 1.0953 inches. Construct a 95 percent confidence interv...

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Q: Find the 90 percent confidence interval for the standard deviation of gasoline

Find the 90 percent confidence interval for the standard deviation of gasoline mileage mpg for these 16 San Francisco commuters driving hybrid gas-electric vehicles.

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Q: (a) Find the standard error of the mean for each

(a) Find the standard error of the mean for each sampling situation (assuming a normal population). (b) What happens to the standard error each time you quadruple the sample size? a. σ = 24, n = 9 b....

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Q: The fat content of a pouch of Keebler Right Bites© Fudge

The fat content of a pouch of Keebler Right Bites© Fudge Shoppe© Mini-Fudge Stripes is normally distributed with a mean of 3.50 grams. Assume a known standard deviation of 0.25 gram. (a) What is the s...

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Q: The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder

The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder 3.5 L automatic 5-speed using premium fuel is a normally distributed random variable with a mean of μ = 25.0 MPG and a standard deviation of σ =...

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Q: Construct a confidence interval for μ assuming that each sample is from

Construct a confidence interval for μ assuming that each sample is from a normal population. a. x bar = 14, σ = 4, n = 5, 90 percent confidence b. x bar = 37, σ = 5, n = 15, 99 percent confidence c....

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Q: If you repeated a hypothesis test 1,000 times (in

If you repeated a hypothesis test 1,000 times (in other words, 1,000 different samples from the same population), how many times would you expect to commit a Type I error, assuming the null hypothesis...

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Q: The average age of a part-time seasonal employee at a

The average age of a part-time seasonal employee at a Vail Resorts ski mountain has historically been 37 years. State the hypotheses one would use to test if this average has decreased since the last...

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Q: Sketch a diagram of the decision rule for each pair of hypotheses

Sketch a diagram of the decision rule for each pair of hypotheses. a. H0: μ >80 versus H1: μ < 80 b. H0: μ = 80 versus H1: μ ≠ 80 c. H0: μ < 80 versus H1: μ > 80

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Q: The Ball Corporation’s aluminum can manufacturing facility in Ft. Atkinson,

The Ball Corporation’s aluminum can manufacturing facility in Ft. Atkinson, Wisconsin, wants to use a sample to perform a two-tailed test to see whether the mean incoming metal thickness is at the tar...

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Q: The time it takes a ski patroller to respond to an accident

The time it takes a ski patroller to respond to an accident call has an exponential distribution with an average equal to 5 minutes. (a) In what time will 90 percent of all ski accident calls be respo...

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Q: Find the zcalc test statistic for each hypothesis test. A

Find the zcalc test statistic for each hypothesis test. A. x bar = 242, μ0 = 230, σ = 18, n = 20 B. x bar = 3.44, μ0 = 3.50, σ = 0.24, n = 40 C. x bar = 21.02, μ0 = 20.00, σ = 2.52, n = 30

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Q: Use Excel to find the critical value of z for each hypothesis

Use Excel to find the critical value of z for each hypothesis test. a. 10 percent level of significance, two-tailed test b. 1 percent level of significance, right-tailed test c. 5 percent level of si...

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Q: Use Excel to find the critical value of z for each hypothesis

Use Excel to find the critical value of z for each hypothesis test. a. α = .05, two-tailed test b. α = .10, right-tailed test c. α = .01, left-tailed test

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Q: Find the zcalc test statistic for each hypothesis test.

Find the zcalc test statistic for each hypothesis test. A. x bar = 423, μ0 = 420, σ = 6, n = 9 B. x bar = 8330, μ0 = 8,344, σ = 48, n = 36 C. x bar = 3.102, μ0 = 3.110, σ = .250, n = 25

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Q: Green Beam Ltd. claims that its compact fluorescent bulbs average no

Green Beam Ltd. claims that its compact fluorescent bulbs average no more than 3.50 mg of mercury. A sample of 25 bulbs shows a mean of 3.59 mg of mercury. (A) Write the hypotheses for a right-tailed...

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Q: Determine the p-value for each test statistic.

Determine the p-value for each test statistic. a. Right-tailed test, z = +1.34 b. Left-tailed test, z = -2.07 c. Two-tailed test, z = -1.69

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Q: Procyon Mfg. produces tennis balls. Weights are supposed to be

Procyon Mfg. produces tennis balls. Weights are supposed to be normally distributed with a mean of 2.035 ounces and a standard deviation of 0.002 ounce. A sample of 25 tennis balls shows a mean weight...

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Q: The lifespan of xenon metal halide arc-discharge bulbs for aircraft

The lifespan of xenon metal halide arc-discharge bulbs for aircraft landing lights is normally distributed with a mean of 3,000 hours and a standard deviation of 500 hours. If a new ballast system sho...

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Q: Find the tcalc test statistic for each hypothesis test. A

Find the tcalc test statistic for each hypothesis test. A. x bar = 14.7, μ0 = 13.0, s = 1.8, n = 12 B. x bar = 241, μ0 = 250, s = 12, n = 8 C. x bar = 2,102, μ0 = 2,000, s = 242, n = 17

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Q: Find the critical value of Student’s t for each hypothesis test.

Find the critical value of Student’s t for each hypothesis test. a. 10 percent level of significance, two-tailed test, n = 21 b. 1 percent level of significance, right-tailed test, n = 9 c. 5 percent...

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Q: Between 11 p.m. and midnight on Thursday night,

Between 11 p.m. and midnight on Thursday night, Mystery Pizza gets an average of 4.2 telephone orders per hour. (a) Find the median waiting time until the next telephone order. (b) Find the upper quar...

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Q: Find the critical value of Student’s t for each hypothesis test.

Find the critical value of Student’s t for each hypothesis test. a. Two-tailed test, n = 18, a = .05 b. Right-tailed test, n = 15, a = .10 c. Left-tailed test, n = 31, a = .01

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Q: Find the tcalc test statistic for each hypothesis test. A

Find the tcalc test statistic for each hypothesis test. A. x bar = 347, μ0 = 349, s = 1.8, n = 9 B. x bar = 45, μ0 = 50, s = 12, n = 16 C. x bar = 4.103, μ0 = 4.004, s = 0.245, n = 25

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Q: Find the p-value using Excel (not Appendix D):

Find the p-value using Excel (not Appendix D): a. t = 1.457, d.f. = 14, right-tailed test b. t = 2.601, d.f. = 8, two-tailed test c. t = 21.847, d.f. = 22, left-tailed test

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Q: Use Excel to find the p-value for each test statistic

Use Excel to find the p-value for each test statistic. a. Right-tailed test, t = 11.677, n = 13 b. Left-tailed test, t = 22.107, n = 5 c. Two-tailed test, t = 21.865, n = 34

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Q: The manufacturer of an airport baggage scanning machine claims it can handle

The manufacturer of an airport baggage scanning machine claims it can handle an average of 530 bags per hour. At α = .05 in a left-tailed test, would a sample of 16 randomly chosen hours with a mean o...

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Q: According to J.D. Power & Associates, the mean

According to J.D. Power & Associates, the mean purchase price of a smartphone device (such as an iPhone or Blackberry) in 2008 was $216. In 2009, a random sample of 20 business managers who owned a sm...

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Q: The number of entrees purchased in a single order at a Noodles

The number of entrees purchased in a single order at a Noodles & Company restaurant has had an historical average of 1.60 entrees per order. On a particular Saturday afternoon, a random sample of 40 N...

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Q: In 2008, a small dealership leased 21 Suburu Outbacks on 2

In 2008, a small dealership leased 21 Suburu Outbacks on 2-year leases. When the cars were returned in 2010, the mileage was recorded (see below). Is the dealer’s mean significantly...

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Q: Calculate the test statistic and p-value for each sample.

Calculate the test statistic and p-value for each sample. A. H0: π = .20 versus H1: π ≠ .20, α 5 .025, p = .28, n = 100 B. H0: π < .50 versus H1: π > .50, α 5 .025, p = .60, n = 90 C. H0: π < .75 vers...

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Q: May normality of the sample proportion p be assumed? Show your

May normality of the sample proportion p be assumed? Show your work. a. H0: π = .30 versus H1: π ≠ .30, n = 20 b. H0: π = .05 versus H1: π ≠ .05, n = 50 c. H0: π = .10 versus H1: π ≠ .10, n = 400

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Q: Find each uniform continuous probability and sketch a graph showing it as

Find each uniform continuous probability and sketch a graph showing it as a shaded area. a. P (X < 10) for U (0, 50) b. P (X > 500) for U (0, 1,000) c. P (25 < X < 45) for U (15, 65)

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Q: In a recent survey, 10 percent of the participants rated Pepsi

In a recent survey, 10 percent of the participants rated Pepsi as being “concerned with my health.” PepsiCo’s response included a new “Smart Spot” symbol on its products that meet certain nutrition cr...

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Q: What is the consequence of a false negative in an inspection of

What is the consequence of a false negative in an inspection of your car’s brakes? Hint: The null hypothesis is the status quo (things are OK).

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Q: A poll of 702 frequent and occasional fliers found that 442 respondents

A poll of 702 frequent and occasional fliers found that 442 respondents favored a ban on cell phones in flight, even if technology permits it. At α = .05, can we conclude that more than half the sampl...

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Q: BriteScreen, a manufacturer of 19-inch LCD computer screens,

BriteScreen, a manufacturer of 19-inch LCD computer screens, requires that on average 99.9 percent of all LCDs conform to its quality standard. In a day’s production of 2,000 units, 4 are defective. (...

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Q: Perfect pitch is the ability to identify musical notes correctly without hearing

Perfect pitch is the ability to identify musical notes correctly without hearing another note as a reference. The probability that a randomly chosen person has perfect pitch is .0005. (a) If 20 studen...

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Q: A sample of size n = 15 has variance s2 = 35

A sample of size n = 15 has variance s2 = 35. At α = .01 in a left-tailed test, does this sample contradict the hypothesis that σ2 = 50?

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Q: A sample of size n = 10 has variance s2 = 16

A sample of size n = 10 has variance s2 = 16. At α = .10 in a two-tailed test, does this sample contradict the hypothesis that σ2 = 24?

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Q: A sample of size n = 19 has variance s2 = 1

A sample of size n = 19 has variance s2 = 1.96. At α = .05 in a right-tailed test, does this sample contradict the hypothesis that σ2 = 1.21?

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Q: pH is a measure of acidity that winemakers must watch. A

pH is a measure of acidity that winemakers must watch. A “healthy wine” should have a pH in the range 3.1 to 3.7. The target standard deviation is σ = 0....

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Q: In U.S. hospitals, the average length of stay

In U.S. hospitals, the average length of stay (LOS) for a diagnosis of pneumonia is 137 hours with a standard deviation of 25 hours. The LOS (in hours) for a sample of 12 pneumonia patients at Santa T...

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Q: A passenger metal detector at Chicago’s Midway Airport gives an alarm 0

A passenger metal detector at Chicago’s Midway Airport gives an alarm 0.5 time a minute. (a) Find the median waiting time until the next alarm. (b) Find the first quartile of waiting time before the n...

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Q: A manufacturer claims that its compact fluorescent bulbs contain an average of

A manufacturer claims that its compact fluorescent bulbs contain an average of 2.5 mg of mercury. Write the hypotheses for a two-tailed test, using the manufacturer’s claim about the mean as the null...

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Q: Noodles & Company is interested in testing whether their new menu design

Noodles & Company is interested in testing whether their new menu design helps reduce the average order time for their customers. Suppose that the average order time prior to the introduction of their...

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Q: Sarah and Bob share a 1,000-minute cell phone

Sarah and Bob share a 1,000-minute cell phone calling plan. (a) Make a stacked dot plot to compare the lengths of cell phone calls by Sarah and Bob during the last week. (b) Describe what the dot plot...

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Q: Which type of data (cross-sectional or time series)

Which type of data (cross-sectional or time series) is each variable? a. Scores of 50 students on a midterm accounting exam last semester. b. Bob’s scores on 10 weekly accounting quizzes last semeste...

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Q: The average weight of a package of rolled oats is supposed to

The average weight of a package of rolled oats is supposed to be at least 18 ounces. A sample of 18 packages shows a mean of 17.78 ounces with a standard deviation of 0.41 ounce. (a) At the 5 percent...

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Q: A hotel installs smoke detectors with adjustable sensitivity in all public guest

A hotel installs smoke detectors with adjustable sensitivity in all public guest rooms. (a) State the null and alternative hypotheses. (b) Define Type I and II errors. (c) What are the consequences of...

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Q: The average age of a part-time seasonal employee at a

The average age of a part-time seasonal employee at a Vail Resorts ski mountain has historically been 37 years. A random sample of 50 part-time seasonal employees in 2010 had a sample mean age of 38.5...

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Q: At Oxnard University, a sample of 18 senior accounting majors showed

At Oxnard University, a sample of 18 senior accounting majors showed a mean cumulative GPA of 3.35 with a standard deviation of 0.25. (a) At α = .05 in a two-tailed test, does this differ significantl...

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Q: Interpret each p-value in your own words: a

Interpret each p-value in your own words: a. p-value = .387, H0: π > .20, H1: π < .20, α = .10 b. p-value = .043, H0: π < .90, H1: π > .90, α = .05 c. p-value = .0012, H0: π = .50, H1: π ≠ .50, α = .0...

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Q: Calculate the test statistic and p-value for each sample.

Calculate the test statistic and p-value for each sample. a. H0: π < .60 versus H1: π > .60, α = .05, x = 56, n = 80 b. H0: π = .30 versus H1: π ≠ .30, α = .05, x = 18, n = 40 c. H0: π > .10 versus H1...

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Q: Between 2 a.m. and 4 a.m.

Between 2 a.m. and 4 a.m. at an all-night pizza parlor, the mean time between arrival of telephone pizza orders is 20 minutes. (a) Find the median wait for pizza order arrivals. (b) Explain why the me...

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Q: In a hospital’s shipment of 3,500 insulin syringes, 14

In a hospital’s shipment of 3,500 insulin syringes, 14 were unusable due to defects. (a) At α = .05, is this sufficient evidence to reject future shipments from this supplier if the hospital’s quality...

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Q: To combat antibiotic resistance, the Quality Improvement Consortium recommends a throat

To combat antibiotic resistance, the Quality Improvement Consortium recommends a throat swab to confirm strep throat before a physician prescribes antibiotics to children under age 5. In a random samp...

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Q: To encourage telephone efficiency, a catalog call center issues a guideline

To encourage telephone efficiency, a catalog call center issues a guideline that at least half of all telephone orders should be completed within 2 minutes. Subsequently, a random sample of 64 telepho...

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Q: The recent default rate on all student loans is 5.2

The recent default rate on all student loans is 5.2 percent. In a recent random sample of 300 loans at private universities, there were 9 defaults. (a) Does this sample show sufficient evidence that t...

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Q: A coin was flipped 12 times and came up heads 10 times

A coin was flipped 12 times and came up heads 10 times. (a) Would we be justified in assuming that the sample proportion p is normally distributed? Explain. (b) Calculate a p-value for the observed sa...

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Q: A quality expert inspects 400 items to test whether the population proportion

A quality expert inspects 400 items to test whether the population proportion of defectives exceeds .03, using a right-tailed test at α = .10. (a) What is the power of this test if the true proportion...

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Q: Repeat the previous exercise, using α = .05. For

Repeat the previous exercise, using α = .05. For each true value of π, is the power higher or lower? Previous exercise: A quality expert inspects 400 items to test whether the population proportion...

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Q: For a certain wine, the mean pH (a measure of

For a certain wine, the mean pH (a measure of acidity) is supposed to be 3.50 with a known standard deviation of σ = .10. The quality inspector examines 25 bottles at random to test whether the pH is...

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Q: What is the consequence of a false positive in a weekly inspection

What is the consequence of a false positive in a weekly inspection of a nuclear plant’s cooling system? Hint: The null hypothesis is the status quo (things are OK).

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Q: Repeat the previous exercise, using α = .05. For

Repeat the previous exercise, using α = .05. For each true value of μ, is the power higher or lower? Previous exercise: For a certain wine, the mean pH (a measure of acidity) is supposed to be 3.50...

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Q: The mean life of a certain computer hard disk in continual use

The mean life of a certain computer hard disk in continual use is 8 years. (a) How long a warranty should be offered if the vendor wants to ensure that not more than 10 percent of the hard disks will...

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Q: The Scottsdale fire department aims to respond to fire calls in 4

The Scottsdale fire department aims to respond to fire calls in 4 minutes or less, on average. State the hypotheses you would use if you had reason to believe that the fire department’s claim is not b...

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Q: Give an example of how statistics might be useful to the person

Give an example of how statistics might be useful to the person in the scenario. a. An auditor is looking for inflated broker commissions in stock transactions. b. An industrial marketer is representi...

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Q: Give an example of how statistics might be useful to the person

Give an example of how statistics might be useful to the person in the scenario. a. A personnel executive is examining job turnover by gender in different restaurants in a fast food chain. b. An intr...

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Q: (a) Should the average business school graduate expect to use

(a) Should the average business school graduate expect to use computers to manipulate data, or is this a job better left to specialists? (b) What problems arise when an employee is weak in quantitativ...

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Q: (a) The table shows the number of days on the

(a) The table shows the number of days on the market for the 36 recent home sales in the city of Sonando Hills. Construct a frequency distribution and histogram, using nice (round) bin limits. (b) Des...

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Q: (a) The table shows raw scores on a state civil

(a) The table shows raw scores on a state civil service exam taken by 24 applicants for positions in law enforcement. Construct a frequency distribution and histogram, using nice (round) bin limits. (...

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Q: The U.S. Public Interest Research Group Education Fund,

The U.S. Public Interest Research Group Education Fund, USPIRG, recently published a report titled The Campus Credit Card Trap: A Survey of College Students about Credit Card Marketing. You can find t...

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Q: Using your favorite web browser, enter the search string “business

Using your favorite web browser, enter the search string “business code of ethics.” List five examples of features that a business ethics code should have.

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Q: (a) Make a frequency distribution and histogram for the 2007

(a) Make a frequency distribution and histogram for the 2007 annual compensation of 40 randomly chosen CEOs (millions of dollars). (b) Describe the shape of the histogram. (c) Identify any unusual val...

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Q: A National Health Interview Survey conducted by the U.S.

A National Health Interview Survey conducted by the U.S. Centers for Disease Control reported that using a cell phone instead of a landline appeared to double a person’s chances of binge drinking. “I...

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Q: Find the interval within which 90

Find the interval within which 90 percent of the sample means would be expected to fall, assuming that each sample is from a normal population. a. μ = 100, σ = 12, n = 36 b. μ = 2,000, σ = 150,...

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Q: A study found that radar detector users have lower accident rates,

A study found that radar detector users have lower accident rates, wear their seat belts more, and even vote more than nonusers. (a) Assuming that the study is accurate, do you think there is cause-an...

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Q: A lottery winner told how he picked his six-digit winning

A lottery winner told how he picked his six-digit winning number (5-6-8-10-22-39): number of people in his family, birth date of his wife, school grade of his 13-year-old daughter, sum of his birth da...

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Q: “Smokers are much more likely to speed, run red lights

“Smokers are much more likely to speed, run red lights, and get involved in car accidents than nonsmokers.” (a) Can you think of reasons why this statement might be misleading? Hint: Make a list of si...

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Q: Which measurement level (nominal, ordinal, interval, ratio)

Which measurement level (nominal, ordinal, interval, ratio) is each of the following variables? Explain. a. Number of employees in the Walmart store in Hutchinson, Kansas. b. Number of merchandise re...

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Q: What logical or ethical problems do you see in these hypothetical scenarios

What logical or ethical problems do you see in these hypothetical scenarios? a. Dolon Privacy Consultants concludes that its employees are not loyal because a few samples of employee e-mails containe...

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Q: Which measurement level (nominal, ordinal, interval, ratio)

Which measurement level (nominal, ordinal, interval, ratio) is each of the following variables? Explain. a. Number of passengers on Delta Flight 833. b. Waiting time (minutes) after gate pushback bef...

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Q: When Pennsylvania repealed a law that required motorcycle riders to wear helmets

When Pennsylvania repealed a law that required motorcycle riders to wear helmets, a news headline reported, “Deaths Soar After Repeal of Helmet Law.” After reading the story, Bill said, “But it’s just...

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Q: Which measurement level (nominal, ordinal, interval, ratio)

Which measurement level (nominal, ordinal, interval, ratio) is the response to each question? If you think that the level of measurement is ambiguous, explain why. a. How would you describe your leve...

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Q: (a) Would the measurement level for the data collected from

(a) Would the measurement level for the data collected from this Microsoft® survey question be nominal, ordinal, interval, or ratio? (b) Would a “6” resp...

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Q: Which measurement level (nominal, ordinal, interval, ratio)

Which measurement level (nominal, ordinal, interval, ratio) is each of the following variables? Explain. a. Number of hits in Game 1 of the next World Series. b. Baltimore’s standing in the American...

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Q: Use the sample information x bar = 2.4, σ

Use the sample information x bar = 2.4, σ = 0.15, n = 9 to calculate the following confidence intervals for μ assuming the sample is from a normal population: (a) 90 percent confidence; (b) 95 percent...

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Q: (a) Make a stem-and-leaf plot for

(a) Make a stem-and-leaf plot for these 24 observations on the number of customers who used a downtown CitiBank ATM during the noon hour on 24 consecutive workdays. (b) Make a dot plot of the ATM data...

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Q: Below are sorted data showing average spending per customer (in dollars

Below are sorted data showing average spending per customer (in dollars) at 74 Noodles & Company restaurants. (a) Construct a frequency distribution. Explain how you chose the number of bins and t...

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Q: (a) Use Excel to prepare a 2-D stacked

(a) Use Excel to prepare a 2-D stacked column chart for television sales by year. Modify the colors, fonts, etc., to make the display effective. (b) Change your graph to a 3-D stacked column chart. Mo...

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Q: (a) Use Excel to prepare a 2-D pie

(a) Use Excel to prepare a 2-D pie chart for these web-surfing data. Modify the default colors, fonts, etc., as you judge appropriate to make the display effective. (b) Right-click the chart area, sel...

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Q: What sources of error might you encounter if you want to know

What sources of error might you encounter if you want to know (a) about the dating habits of college men, so you go to a dorm meeting and ask students how many dates they have had in the last year; (b...

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Q: What kind of survey (mail, telephone, interview, web

What kind of survey (mail, telephone, interview, web, direct observation) would you recommend for each of the following purposes, and why? What problems might be encountered? a. To estimate the propo...

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Q: What kind of survey (mail, telephone, interview, web

What kind of survey (mail, telephone, interview, web, direct observation) would you recommend that a small laundry and dry cleaning business use for each of the following purposes, and why? a. To est...

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Q: (a) Make a stem-and-leaf plot for

(a) Make a stem-and-leaf plot for the number of defects per 100 vehicles for these 32 brands. (b) Make a dot plot of the defects data. (c) Describe these two displays. (Hint: Refer to center, variabil...

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Q: (a) The table shows the number of days on the

(a) The table shows the number of days on the market for the 36 recent home sales in the city of Sonando Hills. Construct a frequency distribution and histogram, using nice (round) bin limits. (b) Des...

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Q: (a) The table shows raw scores on a state civil

(a) The table shows raw scores on a state civil service exam taken by 24 applicants for positions in law enforcement. Construct a frequency distribution and histogram, using nice (round) bin limits. (...

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Q: There is a 70 percent chance that an airline passenger will check

There is a 70 percent chance that an airline passenger will check bags. In the next 16 passengers that check in for their flight at Denver International Airport, find the probability that (a) all will...

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Q: For each value of d.f. look up the value

For each value of d.f. look up the value of Student’s t in Appendix D for the stated level of confidence. How close is the t-value to the corresponding z-value (at the bottom of the column for d.f. =...

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Q: (a) Make a frequency distribution and histogram (using appropriate

(a) Make a frequency distribution and histogram (using appropriate bins) for these 28 observations on the amount spent for dinner for four in downtown Chicago on Friday night. (b) Repeat the exercise...

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Q: (a) Make a frequency distribution and histogram for the monthly

(a) Make a frequency distribution and histogram for the monthly off-campus rent paid by 30 students. (b) Repeat the exercise, using a different number of bins. Which is preferred? Why?

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Q: (a) Make a frequency distribution and histogram for the 2007

(a) Make a frequency distribution and histogram for the 2007 annual compensation of 40 randomly chosen CEOs (millions of dollars). (b) Describe the shape of the histogram. (c) Identify any unusual val...

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Q: For each frequency distribution, suggest “nice” bins. Did

For each frequency distribution, suggest “nice” bins. Did your choice agree with Sturges’ Rule? If not, explain. a. Last week’s MPG for 35 student vehicles (xmin = 9.4, xmax = 38.7). b. Ages of 50 ai...

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Q: Convert each individual data value to a standardized z-score.

Convert each individual data value to a standardized z-score. Is it an outlier? a. Ages of airline passengers: x = 92, μ = 46, σ = 13 b. Accounting exam scores: x = 70, μ = 81, σ = 6 c. Condo rental...

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Q: Convert each individual X data value to a standardized Z value and

Convert each individual X data value to a standardized Z value and interpret it.

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Q: In a regional high school swim meet, women’s times (in

In a regional high school swim meet, women’s times (in seconds) in the 200-yard freestyle ranged from 109.7 to 126.2. Estimate the standard deviation, using the Empirical Rule.

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Q: Find the original data value corresponding to each standardized z-score

Find the original data value corresponding to each standardized z-score.

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Q: CitiBank recorded the number of customers to use a downtown ATM during

CitiBank recorded the number of customers to use a downtown ATM during the noon hour on 32 consecutive workdays. (a) Use Excel or MegaStat to sort and standardize the data. (b) Based on the Empirical...

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Q: An executive’s telephone log showed the lengths of 65 calls initiated during

An executive’s telephone log showed the lengths of 65 calls initiated during the last week of July. (a) Use Excel or MegaStat to sort and standardize the data. (b) Based on the stand...

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Q: A random sample of 10 items is drawn from a population whose

A random sample of 10 items is drawn from a population whose standard deviation is unknown. The sample mean is xbar = 270 and the sample standard deviation is s = 20. Use Appendix D to find the values...

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Q: (a) For each data set, find the mean,

(a) For each data set, find the mean, median, and mode. (b) Discuss anything about the data that affects the usefulness of each statistic as a measure of center.

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Q: On Friday night, the owner of Chez Pierre in downtown Chicago

On Friday night, the owner of Chez Pierre in downtown Chicago noted the amount spent for dinner for 28 four-person tables. (a) Find the mean, median, and mode. (b) Do these measures of center agree? E...

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Q: (a) For each data set, find the median,

(a) For each data set, find the median, midrange, and geometric mean. (b) Are they reasonable measures of central tendency? Explain.

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Q: In the Excel function = TRIMMEAN(Data,.10), how

In the Excel function = TRIMMEAN(Data,.10), how many observations would be trimmed from each end of the sorted data array named Data if (a) n = 41, (b) n = 66, and (c) = 83?

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Q: The Comer-Correr Taco Wagon is only open from 11:

The Comer-Correr Taco Wagon is only open from 11:00 a.m. to 2:00 p.m. on Saturday. The owner kept track of the number of customers served on Saturday for 60 weeks. (a) Visually estimate the quartiles...

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Q: The city of Sonando Hills has 8 police officers. In January

The city of Sonando Hills has 8 police officers. In January, the work-related medical expenses for each officer were 0, 0, 0, 0, 0, 0, 150, 650. (a) Calculate the mean, median, mode, midrange, and geo...

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Q: CitiBank recorded the number of customers to use a downtown ATM during

CitiBank recorded the number of customers to use a downtown ATM during the noon hour on 32 consecutive workdays. (a) Use Excel to find the quartiles. What do they tell you? (b) Find the midhinge. What...

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Q: An executive’s telephone log showed the lengths of 65 calls initiated during

An executive’s telephone log showed the lengths of 65 calls initiated during the last week of July. (a) Use Excel to find the quartiles. What do they tell you? (b) Find the midhinge....

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Q: For each X-Y data set (n 5 12):

For each X-Y data set (n 5 12): (a) Make a scatter plot. (b) Find the sample correlation coefficient. (c) Is there a linear relationship between X and Y? If so, describe it. Note: Use Excel or MegaSta...

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Q: Spirit Airlines kept track of the number of empty seats on flight

Spirit Airlines kept track of the number of empty seats on flight 308 (DEN–DTW) for 10 consecutive trips on each weekday except Friday. (a) Sort the data for each day. (b) Find the mean, median, mode,...

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Q: A random sample of 25 items is drawn from a population whose

A random sample of 25 items is drawn from a population whose standard deviation is unknown. The sample mean is x bar = 850 and the sample standard deviation is s = 15. Use Appendix D to find the valu...

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Q: For a sample of (X, Y) data values,

For a sample of (X, Y) data values, the covariance is 48.724, the standard deviation of X is 11.724, and the standard deviation of Y is 8.244. (a) Find the sample correlation coefficient. (b) What doe...

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Q: For each data set, is the mode a good measure of

For each data set, is the mode a good measure of center? Explain.

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Q: Estimate the mean from this table of grouped data and frequencies:

Estimate the mean from this table of grouped data and frequencies:

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Q: Estimate the mean from the following table of grouped data and frequencies

Estimate the mean from the following table of grouped data and frequencies.

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Q: (a) Find the mean and standard deviation for each sample

(a) Find the mean and standard deviation for each sample. (b) What does this exercise show about the standard deviation? Sample A: 6, 7, 8 Sample B: 61, 62, 63 Sample C: 1,000, 1,001, 1,002

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Q: For each data set: (a) Find the mean.

For each data set: (a) Find the mean. (b) Find the standard deviation, treating the data as a sample. (c) Find the standard deviation, treating the data as a population. (d) What does this exercise sh...

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Q: (a) Find the coefficient of variation for prices of these

(a) Find the coefficient of variation for prices of these three stocks. (b) Which stock has the greatest relative variation? (c) To measure variability, why not just compare the standard deviations?...

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Q: Prof. Hardtack gave four Friday quizzes last semester in his senior

Prof. Hardtack gave four Friday quizzes last semester in his senior tax accounting class. A random sample of 10 student scores is shown for each quiz. (a) Find the sample mean, standard deviation, and...

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Q: For each data set, is the mode a good measure of

For each data set, is the mode a good measure of center? Explain. a. GMAT scores (8 MBA applicants): 490, 495, 542, 587, 599, 622, 630, 641 b. Exam grades (12 students): F, D, C, C, C, C, C, C, B, B,...

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Q: The mean monthly rent of students at Oxnard University is $875

The mean monthly rent of students at Oxnard University is $875 with a standard deviation of $219. (a) John’s rent is $1,325. What is his standardized z-score? (b) Is John’s rent an outlier? (c) How hi...

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Q: A random sample of 16 pharmacy customers showed the waiting times below

A random sample of 16 pharmacy customers showed the waiting times below (in minutes). Find a 90 percent confidence interval for μ, assuming that the sample is from a normal population....

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Q: The mean collection period for accounts receivable at Ephemeral Products is 18

The mean collection period for accounts receivable at Ephemeral Products is 18.5 days with a standard deviation of 4.8 days. (a) What is the standardized z-score for an account that is paid in 30 days...

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Q: For each data set, which best indicates a “typical”

For each data set, which best indicates a “typical” data value (mean, median, either)? a. Days on campus by 11 students: 1, 1, 2, 2, 3, 3, 3, 4, 4, 5, 5 b. P/E ratios of 6 stocks: 1.5, 6.5, 6.6, 7.3,...

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Q: For each data set, which best indicates a “typical”

For each data set, which best indicates a “typical” data value (mean, median, either)?

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Q: Days on the market are shown for the 36 most recent home

Days on the market are shown for the 36 most recent home sales in the city of Sonando Hills. (a) Calculate the mean, median, and mode. (b) Is the distribution skewed? Explain. (c) Is the mode a useful...

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Q: Scores are shown for the most recent state civil service exam taken

Scores are shown for the most recent state civil service exam taken by 24 applicants for positions in law enforcement. (a) Calculate the mean, median, and mode. (b) Is the distribution skewed? Explain...

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Q: Prof. Hardtack gave four Friday quizzes last semester in his 10

Prof. Hardtack gave four Friday quizzes last semester in his 10-student senior tax accounting class. (a) Find the mean, median, and mode for each quiz. (b) Do these measures of center agree? Explain....

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Q: CitiBank recorded the number of customers to use a downtown ATM during

CitiBank recorded the number of customers to use a downtown ATM during the noon hour on 32 consecutive workdays. (a) Find the mean, median, and mode. (b) Do these measures of center agree? Explain. (c...

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Q: Are these characteristics of a student at your university mutually exclusive or

Are these characteristics of a student at your university mutually exclusive or not? Explain. a. A 5 works 20 hours or more, B 5 majoring in accounting b. A 5 born in the United States, B 5 born in C...

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Q: Are these events collectively exhaustive or not? Explain.

Are these events collectively exhaustive or not? Explain. a. A 5 college grad, B 5 some college, C 5 no college b. A 5 born in the United States, B 5 born in Canada, C 5 born in Mexico c. A 5 full-ti...

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Q: Let S be the event that a randomly chosen female aged 18

Let S be the event that a randomly chosen female aged 18–24 is a smoker. Let C be the event that a randomly chosen female aged 18–24 is a Caucasian. Given P(S) = .246, P(C) = .830, and P(S ∩ C) = .232...

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Q: Prof. Green gave three exams last semester. Scores were normally

Prof. Green gave three exams last semester. Scores were normally distributed on each exam. Below are scores for 10 randomly chosen students on each exam. (a) Find the 95 percent confidence interval fo...

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Q: Let C be the event that a randomly chosen adult has some

Let C be the event that a randomly chosen adult has some college education. Let M be the event that a randomly chosen adult is married. Given P(C) = .4, P(M) = .5 and P(C ∩ M) = .24, find each probabi...

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Q: Which pairs of events are independent? a. P

Which pairs of events are independent? a. P(A) = .60, P(B) = .40, P(A ∩ B) = .24. b. P(A) = .90, P(B) = .20, P(A ∩ B) = .18. c. P(A) = .50, P(B) = .70, P(A ∩ B) = .25.

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Q: Given P(J) = .2, P(K

Given P(J) = .2, P(K) = .4 and P(J ∩ K) = .15. (a) Find P(J | K). (b) In this problem, are J and K independent?

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Q: Which pairs of events are independent? a. P

Which pairs of events are independent? a. P(J ) = .50, P(K) = .40, P(J ∩ K ) = .3. b. P(J ) = .60, P(K) = .20, P(J ∩ K ) = .12. c. P(J ) = .15, P(K) = .5, P(J ∩ K ) = .1.

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Bob sets two alarm clocks (battery-powered) to be sure he arises for his Monday 8:00 a.m. accounting exam. There is a 75 percent chance that either clock will wake Bob. (a) What is the probability tha...

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Q: Over 1,000 people try to climb Mt. Everest every

Over 1,000 people try to climb Mt. Everest every year. Of those who try to climb Everest, 31 percent succeed. The probability that a climber is at least 60 years old is .04. The probability that a cli...

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Q: The contingency table below shows the results of a survey of online

The contingency table below shows the results of a survey of online video viewing by age. Find the following probabilities or percentages: a. Probability that a viewer is aged 18–3...

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Q: A survey of 158 introductory statistics students showed the following contingency table

A survey of 158 introductory statistics students showed the following contingency table. Find each event probability. a. P(V) b. P(A) c. P(A > V) d. P(A ∪ V) e. P(A | V) f....

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Q: A survey of 156 introductory statistics students showed the following contingency table

A survey of 156 introductory statistics students showed the following contingency table. Find each event probability. a. P(D) b. P(R) c. P(D > R) d. P(D ∪ R) e. P(R | D) f....

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Q: This contingency table describes 200 business students. Find each probability and

This contingency table describes 200 business students. Find each probability and interpret it in words. a. P(A) b. P(M) c. P(A > M) d. P(F > S) e. P(A | M) f. P(A | F) g. P(F | S) h. P(...

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Q: The diameter of bushings turned out by a manufacturing process is a

The diameter of bushings turned out by a manufacturing process is a normally distributed random variable with a mean of 4.035 mm and a standard deviation of 0.005 mm. A sample of 25 bushings is taken...

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The following contingency table shows average yield (rows) and average duration (columns) for 38 bond funds. For a randomly chosen bond fund, find the probability that: a. The bond fund is long dura...

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Q: A drug test for athletes has a 5 percent false positive rate

A drug test for athletes has a 5 percent false positive rate and a 10 percent false negative rate. Of the athletes tested, 4 percent have actually been using the prohibited drug. If an athlete tests p...

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Q: An airport gamma ray luggage scanner coupled with a neural net artificial

An airport gamma ray luggage scanner coupled with a neural net artificial intelligence program can detect a weapon in suitcases with a false positive rate of 2 percent and a false negative rate of 2 p...

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Q: In the Minnesota Northstar Cash Drawing you pick five different numbers between

In the Minnesota Northstar Cash Drawing you pick five different numbers between 1 and 31. What is the probability of picking the winning combination (order does not matter)? Hint: Count how many ways...

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Q: At Oxnard University, a student ID consists of two letters (

At Oxnard University, a student ID consists of two letters (26 possibilities) followed by four digits (10 possibilities). (a) How many unique student IDs can be created? (b) Would one letter followed...

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Q: A real estate office has 10 sales agents. Each of four

A real estate office has 10 sales agents. Each of four new customers must be assigned an agent. (a) Find the number of agent arrangements where order is important. (b) Find the number of agent arrange...

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Q: Calculate the FPCF for each sample and population size. Can the

Calculate the FPCF for each sample and population size. Can the population be considered effectively infinite in each case? a. N = 450, n = 10 b. N = 300, n = 25 c. N = 1800, n = 280

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Q: Concerns about climate change and CO2 reduction have initiated the commercial production

Concerns about climate change and CO2 reduction have initiated the commercial production of blends of biodiesel (e.g., from renewable sources) and petrodiesel (from fossil fuel). Random samples of 35...

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Q: Use the following information x bar = 3.7, s

Use the following information x bar = 3.7, s = 0.2, n = 1,200, N = 5,800—to calculate confidence intervals for μ assuming the sample is from a normal population: (a) 90 percent confidence; (b) 95 per...

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Q: Police records in the town of Saratoga show that 15 percent of

Police records in the town of Saratoga show that 15 percent of the drivers stopped for speeding have invalid licenses. If 12 drivers are stopped for speeding, find the probability that (a) none will h...

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Q: For each level of precision, find the required sample size to

For each level of precision, find the required sample size to estimate the mean starting salary for a new CPA with 95 percent confidence, assuming a population standard deviation of $7,500 (same as la...

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Q: What sample size would be required to estimate the true proportion of

What sample size would be required to estimate the true proportion of American female business executives who prefer the title “Ms.,” with an error of ±0.025 and 98 percent confidence?

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Q: What sample size would be needed to estimate the true proportion of

What sample size would be needed to estimate the true proportion of students at your college (if you are a student) who are wearing backpacks, with 95 percent confidence and an error of ±0.04?

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Q: How large a sample size would be needed to estimate the percentage

How large a sample size would be needed to estimate the percentage of wireless routers in San Francisco that use data encryption, with an error of ±2 percent and 95 percent confidence?

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Q: The mean potassium content of a popular sports drink is listed as

The mean potassium content of a popular sports drink is listed as 140 mg in a 32-oz bottle. Analysis of 20 bottles indicates a sample mean of 139.4 mg. (a) Write the hypotheses for a two-tailed test o...

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Calculate the test statistic and p-value for each sample. a. H0: μ = 60 versus H1: μ ≠ 60, α = .025, / = 63, σ = 8, n = 16 b. H0: μ > 60 versus H1: μ < 60, α = .05, / = 58, σ = 5, n = 25 c. H0: μ < 6...

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The mean arrival rate of flights at O’Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air tra...

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Q: An airline serves bottles of Galena Spring Water that are supposed to

An airline serves bottles of Galena Spring Water that are supposed to contain an average of 10 ounces. The filling process follows a normal distribution with process standard deviation 0.07 ounce. Twe...

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On the midnight shift, the number of patients with head trauma in an emergency room has the probability distribution shown below. (a) Find P(X > 3). (b) Find P(X < 2). (c) Find P(X < 4). (d) Find P(X...

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Q: Discuss the issues of statistical significance and practical importance in each scenario

Discuss the issues of statistical significance and practical importance in each scenario. a. A process for producing I-beams of oriented strand board used as main support beams in new houses has a mea...

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The target activation force of the buttons on a keyless entry clicker is 1.967 newtons. Variation exists in activation force due to the nature of the manufacturing process. A sample of 9 clickers show...

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Q: A firm decides to test its employees for illegal drugs. (

A firm decides to test its employees for illegal drugs. (a) State the null and alternative hypotheses. (b) Define Type I and II errors. (c) What are the consequences of each type of error, and to whom...

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Q: Estimate the p-value as a range using Appendix D (

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Q: Calculate the test statistic and p-value for each sample.

Calculate the test statistic and p-value for each sample. State the conclusion for the specified α.

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Q: The manufacturer of Glo-More flat white interior latex paint claims

The manufacturer of Glo-More flat white interior latex paint claims one-coat coverage of 400 square feet per gallon on interior walls. A painter keeps careful track of 6 gallons and finds coverage (in...

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What type of data (categorical, discrete numerical, or continuous numerical) is each of the following variables? If there is any ambiguity about the data type, explain why the answer is unclear. a. Th...

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Q: What type of data (categorical, discrete numerical, or continuous

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Q: What type of data (categorical, discrete numerical, or continuous

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Q: Do a two-sample test for equality of means assuming equal

Do a two-sample test for equality of means assuming equal variances. Calculate the p-value. a. Comparison of GPA for randomly chosen college juniors and seniors: /1 = 3.05, s1 = .20, n1 = 15, /2 = 3....

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A special bumper was installed on selected vehicles in a large fleet. The dollar cost of body repairs was recorded for all vehicles that were involved in accidents over a 1-year period. Those with the...

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When tested for compliance with Sarbanes-Oxley requirements for financial records and fraud protection, 14 of 180 publicly traded business services companies failed, compared with 7 of 67 computer har...

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Q: In 2009, a sample of 200 in-store shoppers showed

In 2009, a sample of 200 in-store shoppers showed that 42 paid by debit card. In 2012, a sample of the same size showed that 62 paid by debit card. (a). Formulate appropriate hypotheses to test whet...

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Q: From a telephone log, an executive finds that 36 of 128

From a telephone log, an executive finds that 36 of 128 incoming telephone calls last week lasted at least 5 minutes. She vows to make an effort to reduce the length of time spent on calls. The phone...

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Q: A 30-minute consumer survey mailed to 500 adults aged 25234

A 30-minute consumer survey mailed to 500 adults aged 25234 included a $10 gift certificate to Borders. The same survey was mailed to 500 adults aged 25234 without the gift certificate. There were 185...

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Q: Using the following Excel results: / (

Using the following Excel results: (a). What was the overall sample size? (b). How many groups were there? (c). Write the hypotheses. (d). Find the critical value of F for α = .05....

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Q: A study showed that 36 of 72 cell phone users with a

A study showed that 36 of 72 cell phone users with a headset missed their exit, compared with 12 of 72 talking to a passenger. Construct a 95 percent confidence interval for the difference in proporti...

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Q: A survey of 100 cigarette smokers showed that 71 were loyal to

A survey of 100 cigarette smokers showed that 71 were loyal to one brand, compared to 122 of 200 toothpaste users. Construct a 90 percent confidence interval for the difference in proportions.

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Q: Which samples show unequal variances? Use α = .10 in

Which samples show unequal variances? Use α = .10 in all tests. Show the critical values and degrees of freedom clearly and illustrate the decision rule. a. s1 = 10.2, n1 = 22, s2 = 6.4, n2 = 16, two...

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Q: Which samples show unequal variances? Use α = .05 in

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Q: In trials of an experimental Internet-based method of learning statistics

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Researchers at the Mayo Clinic have studied the effect of sound levels on patient healing and have found a significant association (louder hospital ambient sound level is associated with slower postsu...

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Q: Use MegaStat, MINITAB, or another software package to perform Tukey’s

Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of sig...

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Q: Examine the data below showing the weights (in pounds) of

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Q: Use MegaStat, MINITAB, or another software package to perform Tukey’s

Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of sig...

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Q: Use MegaStat, MINITAB, or another software package to perform Tukey’s

Use MegaStat, MINITAB, or another software package to perform Tukey’s test for significant pairwise differences. Perform the test using both the 5 percent and 1 percent levels of sig...

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Q: Use MegaStat, MINITAB, or another software package to perform Tukey’s

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Q: In a one-factor ANOVA with n1 = 6, n2

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In a one-factor ANOVA with n1 = 7, n2 = 6, n3 = 5, n4 = 5, and n5 = 7, the sample standard deviations were s1 = 12, s2 = 24, s3 = 16, s4 = 46, and s5 = 27. For Hartley’s test: (a). State the hypothe...

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Q: For each data set, use Hartley’s test to test the hypothesis

For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample vari...

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Q: For each data set, use Hartley’s test to test the hypothesis

For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample vari...

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Q: Construct a 95 percent confidence interval for the difference of mean monthly

Construct a 95 percent confidence interval for the difference of mean monthly rent paid by undergraduates and graduate students. What do you conclude?

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Q: For each data set, use Hartley’s test to test the hypothesis

For each data set, use Hartley’s test to test the hypothesis of equal variances, using the 5 percent table of critical values from Table 11.5 and the largest and smallest sample vari...

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Q: Using the following Excel results: / (

Using the following Excel results: (a). What was the overall sample size? (b). How many groups were there? (c). Write the hypotheses. (d). Find the critical value of F for α = .10....

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Q: For each data set, use Hartley’s test to test the hypothesis

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Q: In a one-factor ANOVA with sample sizes n1 = 5

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Q: In a one-factor ANOVA with sample sizes n1 = 8

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Q: For each data set: (a) State the hypotheses

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Q: For each data set: (a) State the hypotheses

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Q: For each data set: (a) State the hypotheses

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Q: For each data set: (a) State the hypotheses

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Q: Consider a one-factor ANOVA with n1 = 9, n2

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Q: Consider a one-factor ANOVA with n1 = 6, n2

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Q: The American Bankers Association reported that, in a sample of 120

The American Bankers Association reported that, in a sample of 120 consumer purchases in France, 60 were made with cash, compared with 26 in a sample of 50 consumer purchases in the United States. Con...

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Q: An experimental surgical procedure is being studied as an alternative to the

An experimental surgical procedure is being studied as an alternative to the old method. Both methods are considered safe. Five surgeons perform the operation on two patients matched by age, sex, and...

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Q: A manufacturing process drills holes in sheet metal that are supposed to

A manufacturing process drills holes in sheet metal that are supposed to be .5000 cm in diameter. Before and after a new drill press is installed, the hole diameter is carefully measured (in cm) for 1...

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Q: This table shows partial results for a one-factor ANOVA,

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Q: A survey of 100 mayonnaise purchasers showed that 65 were loyal to

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Q: A 20-minute consumer survey mailed to 500 adults aged 25

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Q: In preliminary tests of a vaccine that may help smokers quit by

In preliminary tests of a vaccine that may help smokers quit by reducing the “rush” from tobacco, 64 subjects who wanted to quit smoking were given either a placebo or the vaccine. Of the 32 in the pl...

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Q: Blue Box is testing a new “half price on Tuesday”

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Q: The U.S. government’s “Cash for Clunkers” program

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The coach told the high school swim team that times in the 200-yard individual medley in the Division I-AA Swim Championships typically are more than 1/2 second faster than their seed times going into...

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Q: Below is a random sample of shoe sizes for 12 mothers and

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Q: A newly installed automatic gate system was being tested to see if

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Q: Repeat the previous exercise, assuming unequal variances. Calculate the p

Repeat the previous exercise, assuming unequal variances. Calculate the p-value using Excel, and show the Excel formula you used. Previous exercise: Do a two-sample test for equality of means assumi...

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Q: Calculate the test statistic and p-value for a test of

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Q: Calculate the test statistic and p-value for a test of

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Q: Find the sample proportions and test statistic for equal proportions. Find

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Q: Find the test statistic and do the two-sample test for

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Q: In 2006, a sample of 200 in-store shoppers showed

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Q: A survey of 100 mayonnaise purchasers showed that 65 were loyal to

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Q: A 20-minute consumer survey mailed to 500 adults aged 25234

A 20-minute consumer survey mailed to 500 adults aged 25234 included a $5 Starbucks gift certificate. The same survey was mailed to 500 adults aged 25234 without the gift certificate. There were 65 re...

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Q: Is the water on your airline flight safe to drink? It

Is the water on your airline flight safe to drink? It is not feasible to analyze the water on every flight, so sampling is necessary. The Environmental Protection Agency (EPA) found bacterial contamin...

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Q: Below are grade point averages for 25 randomly chosen university business students

Below are grade point averages for 25 randomly chosen university business students during a recent semester. Research question: Are the mean grade point averages the same for students in these four cl...

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Is there a difference in the average number of years’ seniority between returning part-time seasonal employees and returning full-time seasonal employees at a Vail Resorts’ ski mountain? From a random...

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Q: The XYZ Corporation is interested in possible differences in days worked by

The XYZ Corporation is interested in possible differences in days worked by salaried employees in three departments in the financial area. A survey of 23 randomly chosen employees reveals the data sho...

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Q: Mean output of solar cells of three types are measured six times

Mean output of solar cells of three types are measured six times under random light intensity over a period of 5 minutes, yielding the results shown. Research question: Is the mean solar cell output t...

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Q: In a bumper test, three types of autos were deliberately crashed

In a bumper test, three types of autos were deliberately crashed into a barrier at 5 mph, and the resulting damage (in dollars) was estimated. Five test vehicles of each type were crashed, with the re...

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Q: The waiting time (in minutes) for emergency room patients with

The waiting time (in minutes) for emergency room patients with non-life-threatening injuries was measured at four hospitals for all patients who arrived between 6:00 and 6:30 p.m. on a certain Wednesd...

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Q: The results shown below are mean productivity measurements (average number of

The results shown below are mean productivity measurements (average number of assemblies completed per hour) for a random sample of workers at each of three plants. Research question: Are the mean hou...

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Q: Below are results of braking tests of the Ford Explorer on glare

Below are results of braking tests of the Ford Explorer on glare ice, packed snow, and split traction (one set of wheels on ice, the other on dry pavement), using three braking methods. Research quest...

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Q: An MBA director examined GMAT scores for the first 10 MBA applicants

An MBA director examined GMAT scores for the first 10 MBA applicants (assumed to be a random sample of early applicants) for four academic quarters. Research question: Do the mean GMAT scores for earl...

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Q: An ANOVA study was conducted to compare dental offices in five small

An ANOVA study was conducted to compare dental offices in five small towns. The response variable was the number of days each dental office was open last year. Research question: Is there a difference...

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Q: The Environmental Protection Agency (EPA) advocates a maximum arsenic level

The Environmental Protection Agency (EPA) advocates a maximum arsenic level in water of 10 micrograms per liter. Below are results of EPA tests on randomly chosen wells in a suburban Michigan county....

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Q: Is a state’s income related to its high school dropout rate?

Is a state’s income related to its high school dropout rate? Research question: Do the high school dropout rates differ among the five income quintiles?

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Q: The average mpg usage for a 2009 Toyota Prius for a sample

The average mpg usage for a 2009 Toyota Prius for a sample of 10 tanks of gas was 45.5 with a standard deviation of 1.8. For a 2009 Honda Insight, the average mpg usage for a sample of 10 tanks of gas...

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Q: In a bumper test, three test vehicles of each of three

In a bumper test, three test vehicles of each of three types of autos were crashed into a barrier at 5 mph, and the resulting damage was estimated. Crashes were from three angles: head-on, slanted, an...

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Q: The top food snacks consumed by adults aged 18–54 are

The top food snacks consumed by adults aged 18–54 are gum, chocolate candy, fresh fruit, potato chips, breath mints/candy, ice cream, nuts, cookies, bars, yogurt, and crackers. Out of a random sample...

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Q: In an early home game, an NBA team made 66 of

In an early home game, an NBA team made 66 of their 94 free throw attempts. In one of their last home games, the team made 68 of 89 attempts. (a). At α = .10, did the team significantly improve its...

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Q: Are college students more likely than young children to eat cereal?

Are college students more likely than young children to eat cereal? Researchers surveyed both age groups to find the answer. The results are shown in the table below. (a). State the hypotheses used...

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Q: A 2005 study found that 202 women held board seats out of

A 2005 study found that 202 women held board seats out of a total of 1,195 seats in the Fortune 100 companies. A 2003 study found that 779 women held board seats out of a total of 5,727 seats in the F...

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Q: A study of the Fortune 100 board of director members showed that

A study of the Fortune 100 board of director members showed that there were 36 minority women holding board seats out of 202 total female board members. There were 142 minority men holding board seats...

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Q: To test his hypothesis that students who finish an exam first get

To test his hypothesis that students who finish an exam first get better grades, a professor kept track of the order in which papers were handed in. Of the first 25 papers, 10 received a B or better c...

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Q: How many full-page advertisements are found in a magazine?

How many full-page advertisements are found in a magazine? In an October issue of Muscle and Fitness, there were 252 ads, of which 97 were full-page. For the same month, the magazine Glamour had 342 a...

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Q: eShopNet, an online clothing retailer, is testing a new e

eShopNet, an online clothing retailer, is testing a new e-mail campaign by sending one version of the e-mail with the word “free” in the subject line (version A) to a group of 1500 customers and anoth...

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Q: After John F. Kennedy Jr. was killed in an airplane

After John F. Kennedy Jr. was killed in an airplane crash at night, a survey was taken, asking whether a noninstrument-rated pilot should be allowed to fly at night. Of 409 New York State residents, 6...

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Q: When the background music tempo was slow, the mean amount of

When the background music tempo was slow, the mean amount of bar purchases for a sample of 17 restaurant patrons was $30.47 with a standard deviation of $15.10. When the background music tempo was fas...

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Q: A ski company in Vail owns two ski shops, one on

A ski company in Vail owns two ski shops, one on the east side and one on the west side. Sales data showed that at the eastern location there were 56 pairs of large gloves sold out of 304 total pairs...

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Q: At a University of Colorado woman’s home basketball game, a random

At a University of Colorado woman’s home basketball game, a random sample of 25 concession purchases showed a mean of $7.12 with a standard deviation of $2.14. For the next week’s home game, the admis...

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Q: Vail Resorts tracks the proportion of seasonal employees who are rehired each

Vail Resorts tracks the proportion of seasonal employees who are rehired each season. Rehiring a seasonal employee is beneficial in many ways, including lowering the costs incurred during the hiring p...

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Q: Does a “follow-up reminder” increase the renewal rate

Does a “follow-up reminder” increase the renewal rate on a magazine subscription? A magazine sent out 760 subscription renewal notices (without a reminder) and got 703 renewals. As an experiment, they...

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Q: A study revealed that the 30-day readmission rate was 31

A study revealed that the 30-day readmission rate was 31.5 percent for 400 patients who received after-hospital care instructions (e.g., how to take their medications) compared to a readmission rate o...

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Q: In a marketing class, 44 student members of virtual (Internet

In a marketing class, 44 student members of virtual (Internet) project teams (group 1) and 42 members of face-to-face project teams (group 2) were asked to respond on a 1–5 scale to the question: “As...

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Q: In San Francisco, a sample of 3,200 wireless routers

In San Francisco, a sample of 3,200 wireless routers showed that 1,312 used encryption (to prevent hackers from intercepting information). In Seattle, a sample of 1,800 wireless routers showed that 68...

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Q: Former U.S. Vice President Dick Cheney received a lot

Former U.S. Vice President Dick Cheney received a lot of publicity after his fourth heart attack. A portable defibrillator was surgically implanted in his chest to deliver an electric shock to restore...

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Q: In 2009 Noodles & Company introduced spaghetti and meatballs to their menu

In 2009 Noodles & Company introduced spaghetti and meatballs to their menu. Before putting it on the menu, they performed taste tests to determine the best-tasting spaghetti sauce. In a paired compari...

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Q: Has the cost to outsource a standard employee background check changed?

Has the cost to outsource a standard employee background check changed? A random sample of 10 companies in spring 2010 showed a sample average of $105 with a sample standard deviation equal to $32. A...

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Q: Are women’s feet getting bigger? Retailers in the last 20 years

Are women’s feet getting bigger? Retailers in the last 20 years have had to increase their stock of larger sizes. Wal-Mart Stores, Inc., and Payless Shoe Source, Inc., have been aggr...

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Q: From her firm’s computer telephone log, an executive found that the

From her firm’s computer telephone log, an executive found that the mean length of 64 telephone calls during July was 4.48 minutes with a standard deviation of 5.87 minutes. She vowed to make an effor...

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Q: An experimental bumper was designed to reduce damage in low-speed

An experimental bumper was designed to reduce damage in low-speed collisions. This bump er was installed on an experimental group of vans in a large fleet, but not on a control group. At the end of a...

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Q: Based on the sample data below, is the average Medicare spending

Based on the sample data below, is the average Medicare spending in the northern region significantly less than the average spending in the southern region at the 1 percent level? (a). State the hy...

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Q: In a 15-day survey of air pollution in two European

In a 15-day survey of air pollution in two European capitals, the mean particulate count (micrograms per cubic meter) in Athens was 39.5 with a standard deviation of 3.75, while in London the mean was...

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Q: One group of accounting students took a distance learning class, while

One group of accounting students took a distance learning class, while another group took the same course in a traditional classroom. At α = .10, is there a significant difference in the...

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Q: Do male and female school superintendents earn the same pay? Salaries

Do male and female school superintendents earn the same pay? Salaries for 20 males and 17 females in a certain metropolitan area are shown below. At α 5= .01, were the mean superintenden...

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Q: The average take-out order size for Ashoka Curry House restaurant

The average take-out order size for Ashoka Curry House restaurant is shown. Assuming equal variances, at α = .05, is there a significant difference in the order sizes? (a). State the...

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Q: Cash withdrawals from a college credit union for a random sample of

Cash withdrawals from a college credit union for a random sample of 30 Fridays and 30 Mondays are shown. At α = .01, is there a difference in the mean withdrawal on Monday and Friday?...

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Q: In MiniCase 10.2, we found that the mean methane

In MiniCase 10.2, we found that the mean methane gas emissions for the two pneumatic controller manufacturers were not equal. When choosing formula 10.3 to calculate the t statistic, we assumed that t...

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Q: A ski company in Vail owns two ski shops, one on

A ski company in Vail owns two ski shops, one on the west side and one on the east side of Vail. Is there a difference in daily average goggle sales between the two stores? Assume equal variances....

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Q: Researchers analyzed 12 samples of two kinds of Stella’s decaffeinated coffee.

Researchers analyzed 12 samples of two kinds of Stella’s decaffeinated coffee. The caffeine in a cup of decaffeinated espresso had a mean of 9.4 mg with a standard deviation of 3.2 mg, while brewed de...

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Q: A ski company in Vail owns two ski shops, one on

A ski company in Vail owns two ski shops, one on the west side and one on the east side of Vail. Ski hat sales data (in dollars) for a random sample of 5 Saturdays during the 2004 season showed the fo...

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Q: Emergency room arrivals in a large hospital showed the statistics below for

Emergency room arrivals in a large hospital showed the statistics below for 2 months. At α = .05, has the variance changed? Show all steps clearly, including an illustration of the decis...

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Q: Concerned about graffiti, mayors of nine suburban communities instituted a citizen

Concerned about graffiti, mayors of nine suburban communities instituted a citizen Community Watch program. (a). State the hypotheses to see whether the number of graffiti incidents declined. (b)....

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Q: A certain company will purchase the house of any employee who is

A certain company will purchase the house of any employee who is transferred out of state and will handle all details of reselling the house. The purchase price is based on two assessments, one assess...

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Q: Nine homes are chosen at random from real estate listings in two

Nine homes are chosen at random from real estate listings in two suburban neighborhoods, and the square footage of each home is noted in the following table. At the .10 level of significance, is there...

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Q: Two labs produce 1280 3 1024 LCD displays. At random,

Two labs produce 1280 3 1024 LCD displays. At random, records are examined for 12 independently chosen hours of production in each lab, and the number of bad pixels per thousand displays is recorded....

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Q: A cognitive retraining clinic assists outpatient victims of head injury, anoxia

A cognitive retraining clinic assists outpatient victims of head injury, anoxia, or other conditions that result in cognitive impairment. Each incoming patient is evaluated to establish an appropriate...

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Q: Rates of return (annualized) in two investment portfolios are compared

Rates of return (annualized) in two investment portfolios are compared over the last 12 quarters. They are considered similar in safety, but portfolio B is advertised as being “less...

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Q: Is there a difference between the variance in ages for full-

Is there a difference between the variance in ages for full-time seasonal employees and part-time seasonal employees at Vail Resorts? A sample of 62 full-time employees had an s12 = 265.69. A sample o...

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Q: As a volunteer for a consumer research group, LaShonda was assigned

As a volunteer for a consumer research group, LaShonda was assigned to analyze the freshness of three brands of tortilla chips. She examined four randomly chosen bags of chips for four brands of chips...

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Q: On a random basis, Bob buys a small take-out

On a random basis, Bob buys a small take-out coffee from one of two restaurants. As a statistics project in the month of May, he measured the temperature of each cup immediately after purchase, using...

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Three samples of each of three types of PVC pipe of equal wall thickness are tested to failure under three temperature conditions, yielding the results shown below. Research questions: Is mean burst s...

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One group of accounting students used simulation programs, while another group received a tutorial. Scores on an exam were compared. (a). Construct a 90 percent confidence interval for the true dif...

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Advertisers fear that users of DVD recorders will “fast forward” past commercials when they watch a recorded program. A leading British pay television company told their advertisers that this effect m...

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Q: Below are data on truck production (number of vehicles completed)

Below are data on truck production (number of vehicles completed) during the second shift at five truck plants for each day in a randomly chosen week. Research question: Are the mean production rates...

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Q: Do positive emotions reduce susceptibility to colds? Healthy volunteers were divided

Do positive emotions reduce susceptibility to colds? Healthy volunteers were divided into two groups based on their emotional profiles and each group was exposed to rhinovirus (the common cold). Of th...

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Q: Male and female students in a finance class were asked how much

Male and female students in a finance class were asked how much their last tank of gas cost. Can you conclude that on average males spent more on gas than females? Males ………………………………………………………… Femal...

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Q: Students in nutrition classes at two high schools were asked to keep

Students in nutrition classes at two high schools were asked to keep track of the number of times during the past month that they ordered from a fast-food chain restaurant. Sonando High School ……………...

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Q: A retailer compared the frequency of customer merchandise returns at two locations

A retailer compared the frequency of customer merchandise returns at two locations. Last month, store A had 57 returns on 760 purchases, while store B had 62 returns on 1,240 purchases. At α = .01, wa...

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Q: Streeling University surveyed a random sample of employees to estimate the frequency

Streeling University surveyed a random sample of employees to estimate the frequency of sexually inappropriate comments they had heard at work during the last month. 32 of 80 respondents said they had...

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The Fischer Theatre compared attendance at its Saturday and Sunday matinee performances of a major Broadway musical. At α = .05, is the Sunday matinee attendance significantly greater th...

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For a marketing class term project, Bob is investigating whether college seniors eat less frequently in fast-food chains than college freshmen. He asked 11 freshmen and 11 seniors to keep track of how...

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Random samples of tires being replaced by a car dealer showed the tire life (miles) below, based on whether or not the owner had checked once a month for recommended tire inflation. Use α...

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To check pain-relieving medications for potential side effects on blood pressure, it is decided to give equal doses of each of four medications to test subjects. To control for the potential effect of...

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To assess the effects of instructor and student gender on student course scores, an experiment was conducted in 11 sections of managerial accounting classes ranging in size from 25 to 66 students. The...

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In a market research study, members of a consumer test panel are asked to rate the visual appeal (on a 1 to 10 scale) of the texture of dashboard plastic trim in a mockup of a new fuel cell car. The m...

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Q: (a) What kind of ANOVA is this (one-

(a) What kind of ANOVA is this (one-factor, two-factor, or two-factor with replication)? (b) Calculate each F test statistic. Calculate the p-value for each F test using Excel’s fun...

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Q: Here is an Excel ANOVA table for an experiment to assess the

Here is an Excel ANOVA table for an experiment to assess the effects of ambient noise level and plant location on worker productivity. (a). What kind of ANOVA is this (one-factor, two-factor, two-f...

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Q: Several friends go bowling several times per month. They keep track

Several friends go bowling several times per month. They keep track of their scores over several months. An ANOVA was performed. (a). What kind of ANOVA is this (one-factor, two-factor, etc.)? (b)...

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Q: Air pollution (micrograms of particulate per ml of air) was

Air pollution (micrograms of particulate per ml of air) was measured along four freeways at each of five different times of day, with the results shown below. (a). What kind of ANOVA is this (one f...

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Q: A company has several suppliers of office supplies. It receives several

A company has several suppliers of office supplies. It receives several shipments each quarter from each supplier. The time (days) between order and delivery was recorded for several randomly chosen s...

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Q: Several friends go bowling several times per month. They keep track

Several friends go bowling several times per month. They keep track of their scores over several months. An ANOVA was performed. (a). What kind of ANOVA is this (one-factor, two-factor, etc.)? (b)...

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Q: Which type of statistic (descriptive, inferential) is each of

Which type of statistic (descriptive, inferential) is each of the following? a. Estimating the default rate on all U.S. mortgages from a random sample of 500 loans. b. Reporting the percent of studen...

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Q: Which statement is false? Explain. a. Sampling

Which statement is false? Explain. a. Sampling error can be reduced by using appropriate data coding. b. Selection bias means that respondents are not typical of the target population. c. Simple rand...

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Q: (a) Use Excel, MegaStat, or MINITAB to fit

(a) Use Excel, MegaStat, or MINITAB to fit an m-period moving average to the exchange rate data shown below with m = 2, 3, 4, and 5 periods. Make a line chart. (b) Which value of m do you prefer? Why?...

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Refer to exercise 14.26. (a) Plot the dollar/pound exchange rate data. Make the graph nice, then copy and paste it so you have four copies. (b) Use MegaStat or MINITAB to perform a simple exponential...

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(a) Plot the data on gas bills. (b) Can you see seasonal patterns? Explain. (c) Use MegaStat or MINITAB to calculate estimated seasonal indexes and trend. (d) Which months are the most expensive? The...

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Q: (a) Plot the data on air travel delays. (

(a) Plot the data on air travel delays. (b) Can you see seasonal patterns? Explain. (c) Use MegaStat or MINITAB to calculate estimated seasonal indexes and trend. (d) Which months have the most delays...

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Q: (a) Plot the data on airplane shipments. (b

(a) Plot the data on airplane shipments. (b) Can you see seasonal patterns? Explain. (c) Use MegaStat or MINITAB to calculate estimated seasonal indexes and trend. Is there a trend in the deseasonaliz...

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Q: (a) Plot the data on revolving credit (credit cards

(a) Plot the data on revolving credit (credit cards and home equity lines of credit are the two major types of revolving credit). (b) Use MegaStat or MINITAB to calculate seasonal indexes and trend. I...

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Q: (a) Use MegaStat or MINITAB to deseasonalize the quarterly data

(a) Use MegaStat or MINITAB to deseasonalize the quarterly data on Coca-Cola’s revenues and fit a trend. Interpret the results. (b) Use MegaStat or MINITAB to perform a regression us...

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Q: (a) Use MegaStat or MINITAB to perform a regression using

(a) Use MegaStat or MINITAB to perform a regression using seasonal binaries. Interpret the results. (b) Make monthly forecasts for 2010. If you can find data on the web, check your forecasts.

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A newspaper article listed nutritional facts for 56 frozen dinners. From that list, 16 frozen dinners were randomly selected by using the random number method. Research question: Choose any two variab...

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Q: The table below shows ratings of 18 movies by two reviewers (

The table below shows ratings of 18 movies by two reviewers (on a 0 to 5 ✰ scale using half ✰ increments). Research question: At α = .05, based on these...

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Q: The management of a theme park obtained a random sample of the

The management of a theme park obtained a random sample of the ages of 36 riders of its Space Adventure Simulator. (a). Make a nice histogram. (b). Did your histogram follow Sturgesâ€&#...

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Q: Are gasoline prices a potential policy tool in controlling carbon emissions?

Are gasoline prices a potential policy tool in controlling carbon emissions? The table below shows 2001 gasoline prices (dollars per liter) and carbon dioxide emissions per dollar of GDP. Research que...

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Q: Below are the top 20 U.S. football teams in

Below are the top 20 U.S. football teams in the seventh and eighth weeks of a recent season, along with the points awarded to each team by a poll of coaches. Research question: At α = .0...

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Q: A supplier of laptop PC power supplies uses a control chart to

A supplier of laptop PC power supplies uses a control chart to track the output (in watts) of each unit produced. The pattern below shows whether each unit’s output was above (A) or below (B) the desi...

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Q: A basketball player took 35 free throws during the season. Her

A basketball player took 35 free throws during the season. Her sequence of hits (H) and misses (M) is shown. Research question: At α = .01, is her hit/miss sequence random? H M M H H M H M M H H H H H...

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Q: Are the variables cross-sectional data or time-series data

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Q: How do you imagine the data were collected? /

How do you imagine the data were collected? Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Score …â€&...

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Q: Is the sample size sufficient to yield a good estimate? If

Is the sample size sufficient to yield a good estimate? If not, do you think more data could easily be obtained, given the nature of the problem? Midterm and Final Exam Scores for Business Statistic...

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Q: State you’re a priori hypothesis about the sign of the slope.

State you’re a priori hypothesis about the sign of the slope. Is it reasonable to suppose a cause and effect relationship? Midterm and Final Exam Scores for Business Statistics Stu...

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Q: (a). Make a histogram (or normal probability plot)

(a). Make a histogram (or normal probability plot) of the residuals and discuss its appearance. (b). Do you see evidence that your regression may violate the assumption of normal errors? Midterm and...

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Q: A model was developed to predict the length of a sentence (

A model was developed to predict the length of a sentence (the response variable) for a male convicted of assault using the following predictor variables: age (in years), number of prior felony convic...

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Q: The data set below shows a sample of salaries for 39 engineers

The data set below shows a sample of salaries for 39 engineers employed by the Solnar Company along with each engineer’s years of experience. (a). Construct a scatter plot using S...

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Q: Observations are taken on sales of a certain mountain bike in 30

Observations are taken on sales of a certain mountain bike in 30 sporting goods stores. The regression model was Y = total sales (thousands of dollars), X1 = display floor space (square meters), X2 5=...

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Q: The same data set from exercise 13.19 also has gender

The same data set from exercise 13.19 also has gender information for each engineer. The binary variable Male = 1 indicates the engineer is male and Male = 0 indicates the engineer is female. Run the...

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Q: If arrivals follow a Poisson distribution with mean 1.2 arrivals

If arrivals follow a Poisson distribution with mean 1.2 arrivals per minute, find the probability that the waiting time until the next arrival will be (a) less than 1.5 minutes; (b) more than 30 secon...

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Q: Using the “Vail Guest Satisfaction Survey” data, construct a

Using the “Vail Guest Satisfaction Survey” data, construct a correlation matrix of the 11 independent variables. The response variable is ovalue. (a). Identify the four pairs of independent variable...

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Q: Which would be “high leverage” observations? a

Which would be “high leverage” observations? a. Leverage hi = .15 in a regression with 5 predictors and 72 observations. b. Leverage hi = .18 in a regression with 4 predictors and 100 observations. c...

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Q: Which violations of regression assumptions, if any, do you see

Which violations of regression assumptions, if any, do you see in these residual diagnostics? Explain.

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Q: Vail Resorts asked a random sample of guests to rate their satisfaction

Vail Resorts asked a random sample of guests to rate their satisfaction on various attributes of their visit on a scale of 1–5 with 1 = very unsatisfied and 5 = very satisfied. The estimated regressio...

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Q: A regression model to predict Y, the state-by-

A regression model to predict Y, the state-by-state 2005 burglary crime rate per 100,000 people, used the following four state predictors: X1 = median age in 2005, X2 = number of 2005 bankruptcies per...

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Q: Inspect the residual plot to check for heteroscedasticity and report your conclusions

Inspect the residual plot to check for heteroscedasticity and report your conclusions. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exa...

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Q: Refer to the ANOVA table below. (a) State the

Refer to the ANOVA table below. (a) State the degrees of freedom for the F test for overall significance. (b) Use Appendix F to look up the critical value of F for α = .05. (c) Calculate...

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Q: Refer to the ANOVA table below. (a) State the

Refer to the ANOVA table below. (a) State the degrees of freedom for the F test for overall significance. (b) Use Appendix F to look up the critical value of F for α = .05. (c) Calculate...

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Q: Refer to the ANOVA table below. (a) State the

Refer to the ANOVA table below. (a) State the degrees of freedom for the F test for overall significance. (b) Use Appendix F to look up the critical value of F for α = .05. (c) Calculate...

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Q: In 2009, US Airways Flight 1549 made a successful emergency landing

In 2009, US Airways Flight 1549 made a successful emergency landing in the Hudson River, after striking birds shortly after takeoff. Are bird strikes an increasing threat to planes? (a). Make an Ex...

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Q: (a) Make an Excel graph of the data on the

(a) Make an Excel graph of the data on the number of certified organic farms in the United States. (b) Discuss the underlying causes that might explain the trend or pattern. (c) Use Excel, MegaStat, o...

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Q: In the previous problem, find (a) the 95th percentile

In the previous problem, find (a) the 95th percentile of waiting times (i.e., 95 percent below); (b) the first quartile of waiting times; (c) the mean time between arrivals.

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Q: (a) Make an Excel line graph of the data on

(a) Make an Excel line graph of the data on employee work stoppages. (b) Discuss the underlying causes that might explain the trend or pattern. (c) Fit three trends (linear, exponential, quadratic). (...

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Q: (a) Make an Excel line graph of the car dealership

(a) Make an Excel line graph of the car dealership data. (b) Discuss the underlying causes that might explain the trend or pattern. (c) Fit three trends (linear, exponential, quadratic). (d) Would any...

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Q: (a) Plot the data on fruit and vegetable consumption.

(a) Plot the data on fruit and vegetable consumption. (b) Discuss the underlying causes that might explain the trend or pattern. (c) Fit a linear trend to the data. (d) Interpret the trend equation. W...

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Q: (a) Make an Excel line graph of the exchange rate

(a) Make an Excel line graph of the exchange rate data. Describe the pattern. (b) Click on the data and choose Add Trendline > Moving Average. Describe the effect of increasing m (e.g., m = 2, 4, 6...

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Q: Is an autocorrelation test appropriate for your data? If so,

Is an autocorrelation test appropriate for your data? If so, perform an eyeball inspection of residual plot against observation order or a runs test. Midterm and Final Exam Scores for Business Stati...

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Q: (a) Make an Excel line graph of the following bond

(a) Make an Excel line graph of the following bond yield data. Describe the pattern. Is there a consistent trend? (b) Use exponential smoothing (MegaStat, MINITAB, or Excel) with α = .20...

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Q: (a) Use MegaStat or MINITAB to deseasonalize the quarterly data

(a) Use MegaStat or MINITAB to deseasonalize the quarterly data on PepsiCo’s revenues and fit a trend. Interpret the results. (b) Use MegaStat or MINITAB to perform a regression usin...

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Q: (a) Use MegaStat or MINITAB to deseasonalize the monthly Corvette

(a) Use MegaStat or MINITAB to deseasonalize the monthly Corvette sales data and fit a trend. Interpret the results. (b) Use MegaStat or MINITAB to perform a regression using seasonal binaries. Interp...

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Q: A random sample of California residents who had recently visited a car

A random sample of California residents who had recently visited a car dealership were asked which type of vehicle they were most likely to purchase, with the results shown. Research question: At &Ici...

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Q: In a three-digit lottery, each of the three digits

In a three-digit lottery, each of the three digits is supposed to have the same probability of occurrence (counting initial blanks as zeros, e.g., 32 is treated as 032). The table shows the frequency...

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Q: Ages of 56 attendees of a recent Hunger Games movie are shown

Ages of 56 attendees of a recent Hunger Games movie are shown. (a). Form seven age classes (10 to 20, 20 to 30, etc.). Tabulate the frequency of attendees in each class. (b). Calculate expected fr...

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Q: Which statement is correct? Why not the others? a

Which statement is correct? Why not the others? a. The level of significance α is the probability of committing Type I error. b. As the sample size increases, critical values of t.05 increase, gradual...

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Q: Excel was asked to generate 50 Poisson random numbers with mean λ

Excel was asked to generate 50 Poisson random numbers with mean λ = 5. X ……………………………………………………………….. Frequency 0 ……………………………………………………………………………….. 1 1 ……………………………………………………………………………….. 1 2 ………………………………...

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Q: During the 1973–74 hockey season, the Boston Bruins played

During the 1973–74 hockey season, the Boston Bruins played 39 home games and scored 193 points, as shown below. (a). Estimate the mean from the sample. (b). Calculate the expecte...

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Q: At a local supermarket receiving dock, the number of truck arrivals

At a local supermarket receiving dock, the number of truck arrivals per day is recorded for 100 days. (a). Estimate the mean from the sample. (b). Calculate the expected frequencies assuming a Poi...

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Q: Use MegaStat or MINITAB to generate 95 percent confidence and prediction intervals

Use MegaStat or MINITAB to generate 95 percent confidence and prediction intervals for various X-values. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 stu...

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Q: Exam scores of 40 students in a statistics class are shown.

Exam scores of 40 students in a statistics class are shown. (a). Estimate the mean and standard deviation from the sample. (b). Assuming that the data are from a normal distribution, define bins b...

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Q: One Friday night, there were 42 carry-out orders at

One Friday night, there were 42 carry-out orders at Ashoka Curry Express. (a). Estimate the mean and standard deviation from the sample. (b). Assuming that the data are from a normal distribution,...

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Q: Use MINITAB’s Stat > Basic Statistics > Normality Test or other software

Use MINITAB’s Stat > Basic Statistics > Normality Test or other software to obtain a probability plot for the exam score data (see Exercise 15.15). Interpret the probability pl...

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Q: Teenagers make up a large percentage of the market for clothing.

Teenagers make up a large percentage of the market for clothing. Below are data on running shoe ownership in four world regions (excluding China). Research question: At α = .01, does thi...

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Q: Students applying for admission to an MBA program must submit scores from

Students applying for admission to an MBA program must submit scores from the GMAT test, which includes a verbal and a quantitative component. Shown here are raw scores for 100 randomly chosen MBA app...

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Q: Is HDTV ownership related to quantity of purchases of othe r electronics

Is HDTV ownership related to quantity of purchases of othe r electronics? A Best Buy retail outlet collected the following data for a random sample of its recent customers. Research question: At &Icir...

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Q: Marketing researchers sent an advance e-mail notice announcing an upcoming

Marketing researchers sent an advance e-mail notice announcing an upcoming Internet survey and describing the purpose of their research. Half the target customers received the prenotification, followe...

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Q: Last month, 85 percent of the visitors to the Sonora Candy

Last month, 85 percent of the visitors to the Sonora Candy Factory made a purchase in the on-site candy shop after taking the factory tour. This month, a random sample of 500 such visitors showed that...

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Q: U.S. market share for smartphones with larger screens is

U.S. market share for smartphones with larger screens is increasing. As of the first quarter of 2011, smartphones with screens 4 inches or larger had captured 24 percent of the smartphone market. The...

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Q: Market research has shown that Americans will continue to eat out even

Market research has shown that Americans will continue to eat out even in a depressed economy. A market analysis during the most recent recession showed the following distribution of visits to the var...

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Q: Use MegaStat or MINITAB to identify observations with high leverage.

Use MegaStat or MINITAB to identify observations with high leverage. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Score â...

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Q: Advertisers need to know which age groups are likely to see their

Advertisers need to know which age groups are likely to see their ads. Purchasers of 120 copies of Cosmopolitan are shown by age group. Purchaser Age ………………………………………………. Units Sold 18–24 ……………………………...

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Q: One-year sales volume of four similar 20-oz.

One-year sales volume of four similar 20-oz. beverages on a college campus is shown. Beverage ………………………………………………………. Sales (Cases) Frappuccino Coffee ………………………………………………………... 18 Frappuccino Mocha ……...

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Q: Using α = .05, perform a runs test for randomness

Using α = .05, perform a runs test for randomness on the sample data (n = 27). A A B B A A B B A B A A B B B A A B B B B A A B A B B

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Q: The results shown below are mean productivity measurements (average number of

The results shown below are mean productivity measurements (average number of assemblies completed per hour) for a random sample of workers at each of three work stations. (a). At α =...

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Q: Consumers are asked to rate the attractiveness of four potential dashboard surface

Consumers are asked to rate the attractiveness of four potential dashboard surface textures on an interval scale (1 5 least attractive, 10 5 most attractive). Use MegaStat or another software package...

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Q: JavaMax is a neighborhood take-out coffee shop that offers three

JavaMax is a neighborhood take-out coffee shop that offers three sizes. Yesterday’s sales are shown. Use MegaStat or another software package to perform a Friedman test to see whethe...

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Q: Profits of 20 consumer food companies are shown. (a)

Profits of 20 consumer food companies are shown. (a) Convert the data to ranks. Check the column sums. (b) Calculate Spearman’s rank correlation coefficient. Show your calculations....

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Q: Rates of return on 24 mutual funds are shown. (a

Rates of return on 24 mutual funds are shown. (a) Convert the data to ranks. Check the column sums. (b) Calculate Spearman’s rank correlation coefficient. Show your calculations. (c)...

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Q: Weights of 12 randomly chosen Sonora Bars (a type of candy

Weights of 12 randomly chosen Sonora Bars (a type of candy) from assembly line 1 had a mean weight of 56.25 grams (g) with a standard deviation of 0.65 g, while the weights of 12 randomly chosen Sonor...

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Q: Using α = .10, perform a runs test for randomness

Using α = .10, perform a runs test for randomness on the sample data (n = 24). X O X X X X O O O O X O O O X O O O X O O X X O

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Q: Which data would be most suitable for a pie chart? Why

Which data would be most suitable for a pie chart? Why not the others? a. Presidential vote in the last election by party (Democratic, Republican, Other). b. Retail prices of six major brands of colo...

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Q: On a professional certifying exam, there are 25 true-false

On a professional certifying exam, there are 25 true-false questions. The correct answers are T F T T F F F T T F T F T T T F F T T F F T T F T. Research question: At α = .05, is the T/F pattern rando...

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Q: A baseball player was at bat 33 times during preseason exhibition games

A baseball player was at bat 33 times during preseason exhibition games. His pattern of hits (H) and nonhits (N) is shown (a nonhit is a walk or a strikeout). Research question: At = 5 .01, is the pat...

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Q: A sample of 28 student scores on the chemistry midterm exam is

A sample of 28 student scores on the chemistry midterm exam is shown. (a). At α = .10, does the population median differ from 50? Make a worksheet in Excel for your calculations. (b)...

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Q: Final exam scores for a sample of 20 students in a managerial

Final exam scores for a sample of 20 students in a managerial accounting class are shown. (a). At α = .05, is there a difference in the population median scores on the two exams? Make...

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Q: Bob and Tom are “paper investors.” They each “buy

Bob and Tom are “paper investors.” They each “buy” stocks they think will rise in value and “holdâ€...

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Q: An experimental bumper was designed to reduce damage in low-speed

An experimental bumper was designed to reduce damage in low-speed collisions. This bumper was installed on an experimental group of vans in a large fleet, but not on a control group. At the end of a t...

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Q: Samples are shown of volatility (coefficient of variation) for sector

Samples are shown of volatility (coefficient of variation) for sector stocks over a certain period of time. (a). At α = .05, is there a difference in median volatility in these four p...

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Q: (a) To construct control limits for an  chart,

(a) To construct control limits for an  chart, name three ways to estimate σ empirically. (b) Why is the  method often used? (c) Why is the s method the default in MINITAB?

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Q: List four rules for detecting abnormal (special cause) observations in

List four rules for detecting abnormal (special cause) observations in a control chart.

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Q: Which statement is not correct concerning a p-value? Explain

Which statement is not correct concerning a p-value? Explain. a. Ceteris paribus, a larger p-value makes it more likely that H0 will be rejected. b. The p-value shows the risk of Type I error if we r...

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Q: Thirty-four customers at Starbucks either ordered coffee (C)

Thirty-four customers at Starbucks either ordered coffee (C) or did not order coffee (X). Research question: At α = .05, is the sequence random? C X C X C C C C X X X X C X C X C X C C C X C X C C X C...

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Q: Explain the relationship between productivity and quality from a modern perspective.

Explain the relationship between productivity and quality from a modern perspective. How does this differ from the past perspective?

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Q: Look up two of Deming’s 14 points on the Internet and explain

Look up two of Deming’s 14 points on the Internet and explain their meaning.

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Q: Define a measurable aspect of quality for (a) the car

Define a measurable aspect of quality for (a) the car dealership where you bought your car, (b) the bank or credit union where you usually make personal transactions, and (c) the movie theater where y...

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Q: Which type of probability (empirical, classical, subjective) is

Which type of probability (empirical, classical, subjective) is each of the following? a. On a given Friday, the probability that Flight 277 to Chicago is on time is 23.7%. b. Your chance of going to...

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Q: Match each statement to the correct property of an estimator (unbiased

Match each statement to the correct property of an estimator (unbiased, consistent, efficient): a. The estimator “collapses” on the true parameter as n increases. b. The estimator has a relatively sm...

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Q: Explain the difference between common cause variation and special cause variation.

Explain the difference between common cause variation and special cause variation.

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Q: Can zero variation be achieved? Explain.

Can zero variation be achieved? Explain.

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Q: Which statement is true? Why not the others?

Which statement is true? Why not the others? a. The Poisson distribution has two parameters. b. The binomial distribution assumes dependent random trials. c. The uniform distribution has two paramete...

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Q: On the Internet, look up two influential thinkers in quality control

On the Internet, look up two influential thinkers in quality control, and briefly state their contributions.

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Q: Explain the role of statisticians in quality improvement.

Explain the role of statisticians in quality improvement.

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Q: The price of a particular stock over a period of 60 days

The price of a particular stock over a period of 60 days rises (1) or declines (2) in the following pattern. Research question: At α = .05, is the pattern random? + + - - - + + + + + + + - - - - + + -...

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Q: Which statement is correct for a simple regression? Why not the

Which statement is correct for a simple regression? Why not the others? a. A 95% confidence interval (CI) for the mean of Y is wider than the 95% CI for the predicted Y. b. A confidence interval for...

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Q: Which data type (categorical, numerical) is each of the

Which data type (categorical, numerical) is each of the following? a. Your current credit card balance. b. Your college major. c. Your car’s odometer mileage reading today.

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Q: Explain the difference between SQC and SPC.

Explain the difference between SQC and SPC.

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Q: Identify three common quality improvement programs and give their acronyms.

Identify three common quality improvement programs and give their acronyms.

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Q: Which statement is false? Explain. a. In the

Which statement is false? Explain. a. In the hypergeometric distribution, sampling is done without replacement. b. The mean of the uniform distribution is always (a + b)/2. c. We use the geometric dis...

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Q: Name the survey instrument used to measure service quality. What are

Name the survey instrument used to measure service quality. What are the five service quality dimensions?

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Q: Which statement is true for a normal distribution? Why not the

Which statement is true for a normal distribution? Why not the others? a. The shape of the PDF is always symmetric regardless of μ and σ. b. The shape of the CDF resembles a bell-shaped curve. c. Whe...

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Q: What is the difference between an attribute control chart and a variable

What is the difference between an attribute control chart and a variable control chart?

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Q: (a) What determines sampling frequency? (b) Why

(a) What determines sampling frequency? (b) Why are variable samples often small? (c) Why are attribute samples often large?

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Q: Why is the quality improvement process never-ending? Identify the

Why is the quality improvement process never-ending? Identify the steps of one improvement cycle identified in the textbook.

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Q: In a study of stock prices from 1970 to 1994, the

In a study of stock prices from 1970 to 1994, the correlation between Nasdaq closing prices on successive days (i.e., with a 1-day lag) was r = .13 with a t statistic of 5.47. Interpret this result. (...

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Q: Describe two quality improvement tools unique to the service industry.

Describe two quality improvement tools unique to the service industry.

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Q: Tell if each statement is true or false for a simple regression

Tell if each statement is true or false for a simple regression. If false, explain. a. If the standard error is syx = 3,207, then a residual ei = 4,327 would be an outlier. b. In a regression with n...

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Q: Give the type of measurement (nominal, ordinal, interval,

Give the type of measurement (nominal, ordinal, interval, ratio) for each variable. a. Length of time required for a randomly chosen vehicle to cross a toll bridge. b. Student’s ranking of five cell...

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Q: Which is not a characteristic of using a log scale to display

Which is not a characteristic of using a log scale to display time series data? Explain. a. A log scale helps if we are comparing changes in two time series of dissimilar magnitude. b. General busine...

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Q: Which statement is incorrect? Explain. a. The triangular

Which statement is incorrect? Explain. a. The triangular always has a single mode. b. The mean of the triangular is (a + b + c)/3. c. The triangular cannot be skewed left or right.

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Q: Tell if each variable is continuous or discrete. a

Tell if each variable is continuous or discrete. a. Tonnage carried by an oil tanker at sea. b. Wind velocity at 7 o’clock this morning. c. Number of text messages you received yesterday.

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Q: To choose a sample of 12 students from a statistics class of

To choose a sample of 12 students from a statistics class of 36 students, which type of sample (simple random, systematic, cluster, convenience), is each of these? a. Picking every student who was we...

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Q: Which is not an ethical obligation of a statistician? Explain.

Which is not an ethical obligation of a statistician? Explain. a. To know and follow accepted procedures. b. To ensure data integrity and accurate calculations. c. To support client wishes in drawing...

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Q: Why are p charts widely used in service applications like health care

Why are p charts widely used in service applications like health care?

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Q: Make a fishbone chart (cause-and-effect diagram)

Make a fishbone chart (cause-and-effect diagram) like the following for the reasons you have ever been (or could be) late to class. Use as many branches as necessary. Which factors are most important?...

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Q: A forecasting model is fitted to sales data over 24 months.

A forecasting model is fitted to sales data over 24 months. Forecasting errors are tabulated to reveal whether the model provides an overestimate (1) or an underestimate (2) for each month’s sales. Th...

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Q: Make a fishbone chart (cause-and-effect diagram)

Make a fishbone chart (cause-and-effect diagram) for the reasons your end-of-month checkbook balance may not match your bank statement. Use as many branches as necessary. Which factors are most import...

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Q: Make a fishbone chart (cause-and-effect diagram)

Make a fishbone chart (cause-and-effect diagram) for the reasons an airline flight might be late to arrive. Use as many branches as necessary. Which factors are most important? Which are most easily c...

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Q: For a multiple regression, which statement is true? Why not

For a multiple regression, which statement is true? Why not the others? a. Evans’ Rule suggests at least 10 observations for each predictor. b. The tcalc in a test for significance of a binary predic...

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Q: A researcher used stepwise regression to create regression models to predict CarTheft

A researcher used stepwise regression to create regression models to predict CarTheft (thefts per 1,000) using four predictors: Income (per capita income), Unem (unemployment percent), Pupil/ Tea (pup...

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Q: Researchers found a correlation coefficient of r = .50 on personality

Researchers found a correlation coefficient of r = .50 on personality measures for identical twins. A reporter interpreted this to mean that “the environment orchestrated one-half of their personality...

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Q: Driving without a seat belt is not risky. I’ve done it

Driving without a seat belt is not risky. I’ve done it for 25 years without an accident.” This best illustrates which fallacy? a. Unconscious bias. b. Conclusion from a small sample. c. Post hoc reas...

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Q: Can people really identify their favorite brand of cola? Volunteers tasted

Can people really identify their favorite brand of cola? Volunteers tasted Coke, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below. Research question: At α = .05, is the cor...

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Q: A survey of randomly chosen new students at a certain university

A survey of randomly chosen new students at a certain university revealed the data below concerning the main reason for choosing this university instead of another. Research question: At Î&plus...

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Q: A survey of 189 statistics students asked the age of car usually

A survey of 189 statistics students asked the age of car usually driven and the student’s political orientation. The car age was a numerical variable, which was converted into ordina...

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Q: The actual distribution of car colors for 2006 model car buyers is

The actual distribution of car colors for 2006 model car buyers is shown below. Based on the sample of 200 car buyers for 2012 model vehicles, use the multinomial chi-square GOF test at α...

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Q: Make a scatter plot of Y against X. Discuss what it

Make a scatter plot of Y against X. Discuss what it tells you. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Score â€&br...

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Q: Are these cross-sectional data or time-series data?

Are these cross-sectional data or time-series data? What is the unit of observation (e.g., firm, individual, year)?

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Q: Prof. Green’s multiple-choice exam had 50 questions with the

Prof. Green’s multiple-choice exam had 50 questions with the distribution of correct answers shown below. Research question: At α = .05, can you reject the hypothesis that Green’s exam answers came fr...

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Q: Oxnard Kortholt, Ltd., employs 50 workers. Research question:

Oxnard Kortholt, Ltd., employs 50 workers. Research question: At α = .05, do Oxnard employees differ significantly from the national percent distribution?

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Q: In a four-digit lottery, each of the four digits

In a four-digit lottery, each of the four digits is supposed to have the same probability of occurrence. The table shows the frequency of occurrence of each digit for 89 consecutive daily four digit d...

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Q: A student rolled a supposedly fair die 60 times, resulting in

A student rolled a supposedly fair die 60 times, resulting in the distribution of dots shown. Research question: At α = .10, can you reject the hypothesis that the die is fair?

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Q: In the World Cup tournaments between 1990 and 2002, there were

In the World Cup tournaments between 1990 and 2002, there were 232 games with the distribution of goals shown in this worksheet. Research question: At α = .025, can you reject the hypoth...

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Q: The table below shows the number of ATM customer arrivals per minute

The table below shows the number of ATM customer arrivals per minute in 60 randomly chosen minutes. Research question: At α = .025, can you reject the hypothesis that the number of arriv...

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Q: (a) Make a scatter plot of the data. What

(a) Make a scatter plot of the data. What does it suggest about the correlation between X and Y? (b) Use Excel, MegaStat, or MINITAB to calculate the correlation coefficient. (c) Use Excel or Appendi...

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Q: Pick one Excel data set (A through F) and investigate

Pick one Excel data set (A through F) and investigate whether the data could have come from a normal population using α = .01. Use any test you wish, including a histogram, or MegaStat&a...

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Q: Explain each chart’s purpose and the parameters that must be known or

Explain each chart’s purpose and the parameters that must be known or estimated to establish its control limits. a.  chart b. R chart c. p chart d. I chart

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Q: Define three possible quality metrics (not necessarily the ones actually used

Define three possible quality metrics (not necessarily the ones actually used) to describe and monitor: (a) your performance in your college classes; (b) effectiveness of the professors in your colleg...

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Q: Are the X and Y data well-conditioned? If not

Are the X and Y data well-conditioned? If not, make any transformations that may be necessary and explain.

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Q: Define three quality metrics that might be used to describe quality and

Define three quality metrics that might be used to describe quality and performance for the following services: (a) your cellular phone service (e.g., Verizon); (b) your Internet service provider (e.g...

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Q: A process has specification limits of LSL = 540 and USL =

A process has specification limits of LSL = 540 and USL = 550. The process standard deviaton is σ = 1.25. Find the Cp and Cpk capability indexes if (a) the process mean is 545; (b) the process mean is...

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Q: In painting an automobile, the thickness of the color coat has

In painting an automobile, the thickness of the color coat has a lower specification limit of 0.80 mil and an upper specification limit of 1.20 mils. Find the Cp and Cpk capability indexes if (a) the...

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Q: Moisture content per gram of a certain baked product has specification limits

Moisture content per gram of a certain baked product has specification limits of 120 mg and 160 mg. Find the Cp and Cpk capability indexes if (a) the process mean is 140 mg and the process standard de...

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Q: Employees of Axolotl Corporation were sampled at random from pay records and

Employees of Axolotl Corporation were sampled at random from pay records and asked to complete an anonymous job satisfaction survey, yielding the tabulation shown. Research question: At α...

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Q: Sixty-four students in an introductory college economics class were asked

Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At &Ici...

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Q: To see whether students who finish an exam first get the same

To see whether students who finish an exam first get the same grades as those who finish later, a professor kept track of the order in which papers were handed in. Of the first 25 papers, 10 received...

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Q: A sample of 200 customers at a supermarket showed that 28 used

A sample of 200 customers at a supermarket showed that 28 used a debit card to pay for their purchases. (a). Find the 95 percent confidence interval for the population proportion. (b). Why is it OK t...

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Q: From 74 of its restaurants, Noodles & Company managers collected data

From 74 of its restaurants, Noodles & Company managers collected data on per-person sales and the percent of sales due to “potstickers” (a popular food item). B...

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Q: A web-based anonymous survey of students asked for a self

A web-based anonymous survey of students asked for a self-rating on proficiency in a language other than English and the student’s frequency of newspaper reading. Research question:...

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Q: State your a priori hypotheses about the sign (+ or -) of

State your a priori hypotheses about the sign (+ or -) of each predictor and your reasoning about cause and effect. Would the intercept have meaning in this problem? Explain.

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Q: A student team examined parked cars in four different suburban shopping malls

A student team examined parked cars in four different suburban shopping malls. One hundred vehicles were examined in each location. Research question: At α = .05, does vehicle type vary...

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Q: Choose either 2 × 2 contingency table shown below (males or

Choose either 2 × 2 contingency table shown below (males or females). Research question: At α = .005, is smoking independent of race? (Smoking rates are from Statistical Abs...

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Q: High levels of cockpit noise in an aircraft can damage the hearing

High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound...

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Q: Forecasters’ interest rate predictions over an eight-year period were studied

Forecasters’ interest rate predictions over an eight-year period were studied to see whether the predictions corresponded to what actually happened. The 2 × 2 contingenc...

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Q: In a study of childhood asthma, 4,317 observations were

In a study of childhood asthma, 4,317 observations were collected on education and smoking during pregnancy, shown in the 4 × 3 contingency table below. Research question: At Î&plus...

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Q: Two contingency tables below show return on investment (ROI) and

Two contingency tables below show return on investment (ROI) and percent of sales growth over the previous 5 years for 85 U.S. firms. ROI is defined as percentage of return on a combination of stockho...

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Q: Based on the cost of sampling and the presumed accuracy required,

Based on the cost of sampling and the presumed accuracy required, would sampling or 100 percent inspection be used to collect data on (a) the horsepower of each engine being installed in new cars; (b)...

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Q: Bob said, “We use the normal distribution to set the

Bob said, “We use the normal distribution to set the control limits for the  chart because samples from processes follow a normal distribution.” Is Bob right? Explain.

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Q: (a) Make a scatter plot of the data. What

(a) Make a scatter plot of the data. What does it suggest about the correlation between X and Y? (b) Use Excel, MegaStat, or MINITAB to calculate the correlation coefficient. (c) Use Excel or Appendi...

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Q: In the following regression, X = weekly pay, Y =

In the following regression, X = weekly pay, Y = income tax withheld, and n = 35 McDonald’s employees. (a) Write the fitted regression equation. (b) State the degrees of freedom for...

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Q: Does your sample size fulfill Evans’ Rule (n/k >

Does your sample size fulfill Evans’ Rule (n/k > 10) or at least Doane’s Rule (n/k > 5)?

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Q: In the following regression, X = monthly maintenance spending (dollars

In the following regression, X = monthly maintenance spending (dollars), Y = monthly machine downtime (hours), and n = 15 copy machines. (a) Write the fitted regression equation. (b) State the degrees...

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Q: In the following regression, X = total assets ($ billions),

In the following regression, X = total assets ($ billions), Y = total revenue ($ billions), and n = 64 large banks. (a) Write the fitted regression equation. (b) State the degrees of freedom for a two...

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Q: Do stock prices of competing companies move together? Below are daily

Do stock prices of competing companies move together? Below are daily closing prices of two computer services firms (IBM = International Business Machines Corporation, HPQ = Hewlett- Packard Company....

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Q: Below are percentages for annual sales growth and net sales attributed to

Below are percentages for annual sales growth and net sales attributed to loyalty card usage at 74 Noodles & Company restaurants. (a) Make a scatter plot. (b) Find the correlation coefficient and...

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Q: Below are fertility rates (average children born per woman) in

Below are fertility rates (average children born per woman) in 15 EU nations for 2 years. (a) Make a scatter plot. (b) Find the correlation coefficient and interpret it. (c) Test the correlation coeff...

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Q: Consider the following Excel regression of perceived sound quality as a function

Consider the following Excel regression of perceived sound quality as a function of price for 27 stereo speakers. (a) Is the coefficient of Price significantly different from zero at α =...

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Q: Choose one of these three data sets. (a) Make

Choose one of these three data sets. (a) Make a scatter plot. (b) Let Excel estimate the regression line, with fitted equation and R2. (c) Describe the fit of the regression. (d) Write the fitted regr...

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Q: Simple regression was employed to establish the effects of childhood exposure to

Simple regression was employed to establish the effects of childhood exposure to lead. The effective sample size was about 122 subjects. The independent variable was the level of dentin lead (parts pe...

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Q: Two manufacturing facilities produce 1280 × 1024 LED (light-emitting

Two manufacturing facilities produce 1280 × 1024 LED (light-emitting diode) displays. Twelve shipments are tested at random from each lab, and the number of bad pixels per billion is note...

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Q: (a) Interpret the slope of the fitted regression HomePrice =

(a) Interpret the slope of the fitted regression HomePrice = 125,000 + 150 SquareFeet. (b) What is the prediction for HomePrice if SquareFeet = 2,000? (c) Would the intercept be meaningful if this reg...

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Q: Perform the regression and write the estimated regression equation (round off

Perform the regression and write the estimated regression equation (round off to 3 or 4 significant digits for clarity). Do the coefficient signs agree with your a priori expectations?

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Q: An experimental bumper was designed to reduce damage in low-speed

An experimental bumper was designed to reduce damage in low-speed collisions. This bumper was installed on an experimental group of vans in a large fleet, but not on a control group. At the end of a t...

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Q: A common belief among faculty is that teaching ratings are lower in

A common belief among faculty is that teaching ratings are lower in large classes. Below are MINITAB results from a regression using Y = mean student evaluation of the professor and X = class size for...

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Q: Below are revenue and profit (both in $ billions) for

Below are revenue and profit (both in $ billions) for nine large entertainment companies. (a). Make a scatter plot of profit as a function of revenue. (b). Use Excel to fit the regression, with fi...

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Q: Below are fitted regressions based on used vehicle ads. Observed ranges

Below are fitted regressions based on used vehicle ads. Observed ranges of X are shown. The assumed regression model is AskingPrice = f (VehicleAge). (a). Interpret the slopes. (b). Are the interce...

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Q: Below are results of a regression of Y = average stock returns

Below are results of a regression of Y = average stock returns (in percent) as a function of X = average price/earnings ratios for the period 1949–1997 (49 years). Separate regressio...

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Q: Adult height is somewhat predictable from average height of both parents.

Adult height is somewhat predictable from average height of both parents. For females, a commonly used equation is YourHeight = ParentHeight - 2.5 while for males the equation is YourHeight = ParentHe...

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Q: The square footage of each of the last 11 homes sold in

The square footage of each of the last 11 homes sold in each of two suburban neighborhoods is noted. Research question: At α = .01, do the medians differ?

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Q: Below are grade point averages for 25 randomly chosen university business students

Below are grade point averages for 25 randomly chosen university business students during a recent semester. Research question: At α = .01, are the median grade point averages the same f...

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Q: In a bumper test, three types of autos were deliberately crashed

In a bumper test, three types of autos were deliberately crashed into a barrier at 5 mph, and the resulting damage (in dollars) was estimated. Five test vehicles of each type were crashed, with the re...

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Q: The waiting time (in minutes) for emergency room patients with

The waiting time (in minutes) for emergency room patients with non-life-threatening injuries was measured at four hospitals for all patients who arrived between 6:00 and 6:30 p.m. on a certain Wednesd...

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Q: Does the 95 percent confidence interval for each predictor coefficient include zero

Does the 95 percent confidence interval for each predictor coefficient include zero? What conclusion can you draw?

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Q: Which of the following is not a reason for sampling? Explain

Which of the following is not a reason for sampling? Explain. a. The destructive nature of some tests. b. High cost of studying the entire population. c. The expense of obtaining random numbers.

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Q: Mean output of arrays of solar cells of three types are measured

Mean output of arrays of solar cells of three types are measured four times under random light intensity over a period of 5 minutes, yielding the results shown below. Research question: At Î&plu...

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Q: Below are results of braking tests of a certain SUV on glare

Below are results of braking tests of a certain SUV on glare ice, packed snow, and split traction (one set of wheels on ice, the other on dry pavement), using three braking methods. Research question:...

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Q: In a call center, the average waiting time for an answer

In a call center, the average waiting time for an answer (in seconds) is shown below by time of day. Research question: At α = .01, does the waiting time differ by day of the week? Only...

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Q: The table below shows annual financial data for a sample of 20

The table below shows annual financial data for a sample of 20 companies in the food consumer products sector. Research question: At α = .01, is there a significant correlation between r...

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Q: Fertility rates (children born per woman) are shown for 27

Fertility rates (children born per woman) are shown for 27 EU member nations in 2 years. Research question: At α = .05, is there a significant rank correlation? Only the first 3 and last...

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Q: (a) Make a line chart for JetBlue’s revenue. (

(a) Make a line chart for JetBlue’s revenue. (b) Describe the trend (if any) and discuss possible causes. (c) Fit both a linear and an exponential trend to the data. (d) Which model...

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Q: (a) Plot both Swiss watch time series on the same

(a) Plot both Swiss watch time series on the same graph. (b) Describe the trend (if any) and discuss possible causes. (c) Fit an exponential trend to each time series. (d) Interpret each fitted trend...

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Q: (a) Plot the total minutes of TV viewing time per

(a) Plot the total minutes of TV viewing time per household. (b) Describe the trend (if any) and discuss possible causes. (c) Fit a linear trend to the data. (d) Would this model give reasonable forec...

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Q: (a) Plot the voter participation rate. (b)

(a) Plot the voter participation rate. (b) Describe the trend (if any) and discuss possible causes. (c) Fit both a linear and a quadratic trend to the data. (d) Which model is preferred? Why? (e) Make...

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Q: If freeway speeds are normally distributed with a mean of μ =

If freeway speeds are normally distributed with a mean of μ = 70 mph and σ = 7 mph, find the probability that the speed of a randomly chosen vehicle (a) exceeds 78 mph; (b) is between 65 and 75 mph; (...

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Q: (a) Choose one category of consumer credit and plot it

(a) Choose one category of consumer credit and plot it. (b) Describe the trend (if any) and discuss possible causes. (c) Fit a trend model of your choice. (d) Make forecasts for 3 years (2011â&#...

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Q: Which statement is correct? Why not the others?

Which statement is correct? Why not the others? a. Likert scales are interval if scale distances are meaningful. b. Cross-sectional data are measured over time. c. A census is always preferable to a...

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Q: (a) Plot the data on U.S. general

(a) Plot the data on U.S. general aviation shipments. (b) Describe the pattern and discuss possible causes. (c) Would a fitted trend be helpful? Explain. (d) Make a similar graph for 1993â€...

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Q: (a) Choose one beverage category and plot the data.

(a) Choose one beverage category and plot the data. (b) Describe the trend (if any) and discuss possible causes. (c) Would a fitted trend be helpful? Explain. (d) Fit several trend models. Which is be...

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Q: (a) Plot either receipts and outlays or federal debt and

(a) Plot either receipts and outlays or federal debt and GDP (plot both time series on the same graph). (b) Describe the trend (if any) and discuss possible causes. (c) Fit a trend of your choice to e...

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Q: (a) Plot both men’s and women’s winning times on the

(a) Plot both men’s and women’s winning times on the same graph. (b) Fit a linear trend model to each series. From the fitted trends, will the times eventually conv...

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Q: A cognitive retraining clinic assists outpatient victims of head injury, anoxia

A cognitive retraining clinic assists outpatient victims of head injury, anoxia, or other conditions that result in cognitive impairment. Each incoming patient is evaluated to establish an appropriate...

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Q: (a) Plot the data on law enforcement officers killed.

(a) Plot the data on law enforcement officers killed. (b) Describe the trend (if any) and discuss possible causes or anomalies in the data. (c) Would a fitted trend be helpful? Explain. (c) Make a for...

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Q: Salaries of 30 randomly chosen individuals in the same occupation (only

Salaries of 30 randomly chosen individuals in the same occupation (only the first 3 and last 3 observations are shown). The data are from a salary equity study comparing two industries. Research quest...

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Q: Does a class break stimulate the pulse? Here are heart rates

Does a class break stimulate the pulse? Here are heart rates for a sample of 30 students before and after a class break. Research question: At α = .05, do the medians differ?

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Q: Do a two-tailed t test for zero slope for each

Do a two-tailed t test for zero slope for each predictor coefficient at α = .05. State the degrees of freedom and look up the critical value in Appendix D (or from Excel). Appendix D:...

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Q: (a) Plot both men’s and women’s winning times on the

(a) Plot both men’s and women’s winning times on the same graph. (b) Fit a linear trend model to each series (men, women). (c) Use Excel’s option...

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Q: (a) Plot U.S. petroleum imports on a

(a) Plot U.S. petroleum imports on a graph. (b) Describe the trend (if any) and discuss possible causes. (c) Fit both a linear and an exponential trend. (c) Interpret each fitted trend equation, expla...

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Q: (a) Which p-values indicate predictor significance at α

(a) Which p-values indicate predictor significance at α = .05? (b) Do the p-values support the conclusions you reached from the t tests? (c) Do you prefer the t test or the p-value appro...

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Q: Based on the R2 and ANOVA table for your model, how

Based on the R2 and ANOVA table for your model, how would you describe the fit?

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Q: Use Excel’s Add Trendline feature to fit a linear regression to the

Use Excel’s Add Trendline feature to fit a linear regression to the scatter plot. Is a linear model credible? Midterm and Final Exam Scores for Business Statistics Students Fall Se...

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Q: Use the standard error to construct an approximate prediction interval for Y

Use the standard error to construct an approximate prediction interval for Y. Based on the width of this prediction interval, would you say the predictions are good enough to have practical value?...

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Q: (a). Generate a correlation matrix for your predictors. Round

(a). Generate a correlation matrix for your predictors. Round the results to three decimal places. (b). Based on the correlation matrix, is collinearity a problem?

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Q: (a). If you did not already do so, rerun

(a). If you did not already do so, rerun the regression requesting variance inflation factors (VIFs) for your predictors. (b). Do the VIFs suggest that multicollinearity is a problem? Explain....

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Q: (a). If you did not already do so, request

(a). If you did not already do so, request a table of standardized residuals. (b). Are any residuals outliers (three standard errors) or unusual (two standard errors)?

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Q: If you did not already do so, request leverage statistics.

If you did not already do so, request leverage statistics. Are any observations influential? Explain.

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Q: If you did not already do so, request a histogram of

If you did not already do so, request a histogram of standardized residuals and/or a normal probability plot. Do the residuals suggest non-normal errors? Explain.

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Q: If you did not already do so, request a plot of

If you did not already do so, request a plot of residuals versus the fitted Y. Is heteroscedasticity a concern?

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Q: Here are the ages of a random sample of 20 CEOs (

Here are the ages of a random sample of 20 CEOs (chief executive officers) of Fortune 500 U.S. corporations. (a). Find the mean, median, and mode. (b). Discuss advantages and disadvantages of each...

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Q: If you are using time-series data, perform one or

If you are using time-series data, perform one or more tests for autocorrelation (visual inspection of residuals plotted against observation order, runs test, Durbin-Watson test). Is autocorrelation a...

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Q: In a model of Ford’s quarterly revenue Total Revenue = β0 +

In a model of Ford’s quarterly revenue Total Revenue = β0 + β1 Car Sales + β2 Truck Sales + β3 SUVSales + ε, the three predictors are measured in number of units sold (not dollars). (a). Interpret ea...

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Q: Which one of the following is true? Why not the others

Which one of the following is true? Why not the others? a. Histograms are useful for visualizing correlations. b. Pyramid charts are generally preferred to bar charts. c. A correlation coefficient ca...

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Q: In a study of paint peel problems, a regression was suggested

In a study of paint peel problems, a regression was suggested to predict defects per million (the response variable). The intended predictors were supplier (four suppliers, coded as binaries) and subs...

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Q: A hospital emergency room analyzed n = 17,664 hourly observations

A hospital emergency room analyzed n = 17,664 hourly observations on its average occupancy rates using six binary predictors representing days of the week and two binary predictors representing the 8-...

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Q: Using test data on 20 types of laundry detergent, an analyst

Using test data on 20 types of laundry detergent, an analyst fitted a regression to predict Cost Per Load (average cost per load in cents per load) using binary predictors Top Load (1 if washer is a t...

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Q: A researcher used stepwise regression to create regression models to predict Birth

A researcher used stepwise regression to create regression models to predict Birth Rate (births per 1,000) using five predictors: LifeExp (life expectancy in years), InfMort (infant mortality rate), D...

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Q: A sports enthusiast created an equation to predict Victories (the team’s

A sports enthusiast created an equation to predict Victories (the team’s number of victories in the National Basketball Association regular season play) using predictors FGP (team fi...

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Q: An expert witness in a case of alleged racial discrimination in a

An expert witness in a case of alleged racial discrimination in a state university school of nursing introduced a regression of the determinants of Salary of each professor for each year during an 8-y...

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Q: Analysis of a Detroit Marathon (n = 1,015 men

Analysis of a Detroit Marathon (n = 1,015 men, n = 150 women) produced the regression results shown below, with dependent variable Time (the marathon time in minutes) and predictors Age (runnerâ...

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Q: Using test data on 43 vehicles, an analyst fitted a regression

Using test data on 43 vehicles, an analyst fitted a regression to predict CityMPG (miles per gallon in city driving) using as predictors Length (length of car in inches), Width (width of car in inches...

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Q: If a random experiment whose success probability is .20 is repeated

If a random experiment whose success probability is .20 is repeated 8 times, find the probability of (a) exactly 3 successes; (b) more than 3 successes; (c) at most 2 successes. (d) Which probability...

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Q: (a) Use Excel’s function =NORM.INV(RAND

(a) Use Excel’s function =NORM.INV(RAND(),0,1) or Excel’s Data Analysis > Random Numbers to generate 100 normally distributed random numbers with a mean of 0 and...

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Q: Interpret the slope. Does the intercept have meaning, given the

Interpret the slope. Does the intercept have meaning, given the range of the data? Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58 students) Midterm Exam Sc...

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Q: (a) Use Excel’s function =RAND() or Excel’s Data

(a) Use Excel’s function =RAND() or Excel’s Data Analysis > Random Numbers to generate 100 uniformly distributed random numbers between 0 and 1. (b) Make a histo...

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Q: (a) Use Excel’s Data Analysis > Random Numbers to generate

(a) Use Excel’s Data Analysis > Random Numbers to generate 100 Poisson-distributed random numbers with a mean of λ = 4. (b) Make a histogram of your sample and assess...

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Q: Refer back to Table 15.11, which shows the distribution

Refer back to Table 15.11, which shows the distribution of the number of U.S. Supreme Court appointments per year from 1900–1999. Since 1999 there have been four Supreme Court appoin...

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Q: The temperature control unit on a commercial freezer in a 24-

The temperature control unit on a commercial freezer in a 24-hour grocery store is set to maintain a mean temperature of 23 degrees Fahrenheit. The temperature varies because people are constantly ope...

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Q: Refer to the freezer data’s 80 individual temperature observations in problem 17

Refer to the freezer data’s 80 individual temperature observations in problem 17.52. Problem 17.52: Refer to the freezer problem 17.51 with μ = 23 and σ =...

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Q: A Nabisco Fig Newton has a process mean weight of 14.

A Nabisco Fig Newton has a process mean weight of 14.00 g with a standard deviation of 0.10 g. The lower specification limit is 13.40 g and the upper specification limit is 14.60 g. (a). Describe th...

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Q: A new type of smoke detector battery is developed. From laboratory

A new type of smoke detector battery is developed. From laboratory tests under standard conditions, the half-life (defined as less than 50 percent of full charge) of 20 batteries are shown below. (a...

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Q: A box of Wheat Chex cereal is to be filled to a

A box of Wheat Chex cereal is to be filled to a mean weight of 466 grams. The lower specification limit is 453 grams (the labeled weight is 453 grams) and the upper specification limit is 477 grams (s...

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Q: For each sample, do a test for zero correlation. (

For each sample, do a test for zero correlation. (a) Use Appendix D to find the critical value of tα. (b) State the hypotheses about ρ. (c) Perform the t test and report your...

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Q: Which statement is true? Why not the others?

Which statement is true? Why not the others? a. We expect the median to exceed the mean in positively skewed data. b. The geometric mean is not possible when there are negative data values. c. The mi...

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Q: Use Excel, MegaStat, or MINITAB to fit the regression model

Use Excel, MegaStat, or MINITAB to fit the regression model, including residuals and standardized residuals. Midterm and Final Exam Scores for Business Statistics Students Fall Semester 2011 (n = 58...

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Q: (a) Make an Excel scatter plot. What does it

(a) Make an Excel scatter plot. What does it suggest about the population correlation between X and Y? (b) Make an Excel worksheet to calculate SSxx, SSyy, and SSxy. Use these sums to calculate the sa...

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Q: (a) Make a scatter plot of the data. What

(a) Make a scatter plot of the data. What does it suggest about the correlation between X and Y? (b) Use Excel, MegaStat, or MINITAB to calculate the correlation coefficient. (c) Use Excel or Appendi...

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Q: Refer to the ANOVA table below. (a) State the

Refer to the ANOVA table below. (a) State the degrees of freedom for the F test for overall significance. (b) Use Appendix F to look up the critical value of F for α = .05. (c) Calculate...

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Q: Observations are taken on net revenue from sales of a certain LCD

Observations are taken on net revenue from sales of a certain LCD TV at 50 retail outlets. The regression model was Y = net revenue (thousands of dollars), X1 = shipping cost (dollars per unit), X2 =...

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Q: Observations are taken on sales of a certain mountain bike in 30

Observations are taken on sales of a certain mountain bike in 30 sporting goods stores. The regression model was Y = total sales (thousands of dollars), X1 = display floor space (square meters), X2 =...

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Q: (a) Interpret the slope of the fitted regression Number of

(a) Interpret the slope of the fitted regression Number of International Franchises = -47.5 + 1.75 Power Distance Index. The Power Distance Index is a measure on a scale of 0–100 of the wealth gap bet...

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Q: The regression equation NetIncome = 2,277 + .0307 Revenue

The regression equation NetIncome = 2,277 + .0307 Revenue was estimated from a sample of 100 leading world companies (variables are in millions of dollars). (a). Interpret the slope. (b). Is the in...

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Q: The regression equation HomePrice = 51.3 + 2.61

The regression equation HomePrice = 51.3 + 2.61 Income was estimated from a sample of 34 cities in the eastern United States. Both variables are in thousands of dollars. HomePrice is the median sellin...

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Q: The regression equation Credits = 15.4 -.07 Work was

The regression equation Credits = 15.4 -.07 Work was estimated from a sample of 21 statistics students. Credits is the number of college credits taken and Work is the number of hours worked per week a...

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Q: Below are fitted regressions for Y = asking price of a used

Below are fitted regressions for Y = asking price of a used vehicle and X = the age of the vehicle. The observed range of X was 1 to 8 years. The sample consisted of all vehicles listed for sale in a...

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Q: (a) Does the 95 percent confidence interval for the slope

(a) Does the 95 percent confidence interval for the slope include zero? If so, what does this tell you? If not, what does it mean? (b) Do a two-tailed t test for zero slope at α = .05. S...

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Q: Which statement is false? Explain. a. If

Which statement is false? Explain. a. If μ = 52 and σ = 15, then X = 81 would be an outlier. b. If the data are from a normal population, about 68 percent of the values will be within μ ± σ. c. If μ...

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Q: A regression model to predict the price of diamonds included the following

A regression model to predict the price of diamonds included the following predictor variables: the weight of the stone (in carats where 1 carat = 0.2 gram), the color rating (D, E, F, G, H, or I), an...

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Q: Refrigerator prices are affected by characteristics such as whether or not the

Refrigerator prices are affected by characteristics such as whether or not the refrigerator is on sale, whether or not it is listed as a Sub-Zero brand, the number of doors (one door or two doors), an...

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Q: (a) Make an Excel worksheet to calculate SSxx, SSyy

(a) Make an Excel worksheet to calculate SSxx, SSyy, and SSxy (the same worksheet you used in exercises 12.2 and 12.3). (b) Use the formulas to calculate the slope and intercept. (c) Use your estimate...

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Q: (a) Make an Excel worksheet to calculate SSxx, SSyy

(a) Make an Excel worksheet to calculate SSxx, SSyy, and SSxy (the same worksheet you used in exercises 12.2 and 12.3). (b) Use the formulas to calculate the slope and intercept. (c) Use your estimate...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data. (b) Select the data points, right-click, select Add Trendline, select the Options tab, and choose Display equation on chart and Display R-squared valu...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data. (b) Select the data points, right-click, select Add Trendline, select the Options tab, and choose Display equation on chart and Display R-squared valu...

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Q: Using the “Metals” data, construct a correlation matrix of

Using the “Metals” data, construct a correlation matrix of the six independent variables. The response variable is Priceylb. (a). Identify any pairs of independent variables that have a significant p...

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Q: (a) Perform a regression using MegaStat or Excel. (

(a) Perform a regression using MegaStat or Excel. (b) State the null and alternative hypotheses for a two-tailed test for a zero slope. (c) Report the p-value and the 95 percent confidence interval fo...

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Q: (a) Perform a regression using MegaStat or Excel. (

(a) Perform a regression using MegaStat or Excel. (b) State the null and alternative hypotheses for a two-tailed test for a zero slope. (c) Report the p-value and the 95 percent confidence interval fo...

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Q: (a) Based on the R2 and ANOVA table for your

(a) Based on the R2 and ANOVA table for your model, how would you assess the fit? (b) Interpret the p-value for the F statistic. (c) Would you say that your model’s fit is good enoug...

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Q: A regression was performed using data on 32 NFL teams. The

A regression was performed using data on 32 NFL teams. The variables were Y = current value of team (millions of dollars) and X = total debt held by the team owners ( millions of dollars). (a) Write t...

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Q: Which probability distribution (uniform, binomial, Poisson) is most

Which probability distribution (uniform, binomial, Poisson) is most nearly appropriate to describe each situation (assuming you knew the relevant parameters)? a. The number of dimes older than 10 yea...

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Q: A regression was performed using data on 16 randomly selected charities.

A regression was performed using data on 16 randomly selected charities. The variables were Y = expenses (millions of dollars) and X = revenue (millions of dollars). (a) Write the fitted regression eq...

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Q: Below is a regression using X = home price (000),

Below is a regression using X = home price (000), Y = annual taxes (000), n = 20 homes. (a) Write the fitted regression equation. (b) Write the formula for each t statistic and verify the t statistics...

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Q: Below is a regression using X = average price, Y =

Below is a regression using X = average price, Y = units sold, n = 20 stores. (a) Write the fitted regression equation. (b) Write the formula for each t statistic and verify the t statistics shown bel...

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Q: (a) Use Excel’s Data Analysis > Regression (or MegaStat

(a) Use Excel’s Data Analysis > Regression (or MegaStat or MINITAB) to obtain regression estimates. (b) Interpret the 95 percent confidence interval for the slope. Does it contain...

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Q: (a) Use Excel’s Data Analysis > Regression (or MegaStat

(a) Use Excel’s Data Analysis > Regression (or MegaStat or MINITAB) to obtain regression estimates. (b) Interpret the 95 percent confidence interval for the slope. Does it contain zero? (c) Interpret...

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Q: (a) Use Excel’s Data Analysis > Regression (or MegaStat

(a) Use Excel’s Data Analysis > Regression (or MegaStat or MINITAB) to obtain regression estimates. (b) Interpret the 95 percent confidence interval for the slope. Does it contain zero? (c) Interpret...

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Q: Refer to the Weekly Earnings data set below. (a)

Refer to the Weekly Earnings data set below. (a) Use MegaStat or MINITAB to find confidence and prediction intervals for Y using the following set of x values: 12, 17, 21, 25, and 30. (b) Report the 9...

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Q: Refer to the Revenue and Profit data set below. Data are

Refer to the Revenue and Profit data set below. Data are in billions of dollars. (a) Use MegaStat or MINITAB to find confidence and prediction intervals for Y using the following set of x values: 1.8,...

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Q: Study the table of residuals. Identify as outliers any standardized residuals

Study the table of residuals. Identify as outliers any standardized residuals that exceed 3 and as unusual any that exceed 2. Can you suggest any reasons for these unusual residuals? Midterm and Fin...

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Q: Review the two residual plots below. Do either of these show

Review the two residual plots below. Do either of these show evidence that the regression error assumptions of normality and constant variation have been violated? Explain.

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Q: Review the two residual plots below. Do either of these show

Review the two residual plots below. Do either of these show evidence that the regression error assumptions of normality and constant variation have been violated? Explain.

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Q: (a) Make an Excel scatter plot. What does it

(a) Make an Excel scatter plot. What does it suggest about the population correlation between X and Y? (b) Make an Excel worksheet to calculate SSxx, SSyy, and SSxy. Use these sums to calculate the sa...

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Q: In the previous problem, calculate (a) the 95th percentile

In the previous problem, calculate (a) the 95th percentile of vehicle speeds (i.e., 95 percent below); (b) the lowest 10 percent of speeds; (c) the highest 25 percent of speeds (3rd quartile).

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Q: Observations are taken on net revenue from sales of a certain LCD

Observations are taken on net revenue from sales of a certain LCD TV at 50 retail outlets. The regression model was Y = net revenue (thousands of dollars), X1 = shipping cost (dollars per unit), X2 =...

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Q: An estimated regression for a random sample of vehicles is MPG =

An estimated regression for a random sample of vehicles is MPG = 49.22 - 0.081 Horsepower, where MPG is miles per gallon and Horsepower is the engine’s horsepower. The standard error is se = 2.03. Sup...

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Q: A sample of season performance measures for 29 NBA teams was collected

A sample of season performance measures for 29 NBA teams was collected for a season. A regression analysis was performed on two of the variables with Y = total number of free throws made and X = total...

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Q: A sample of 74 Noodles & Company restaurants was used to perform

A sample of 74 Noodles & Company restaurants was used to perform a regression analysis with Y = % Annual Revenue Growth and X = % Revenue Due to Loyalty Card Use. Calculate the leverage statistic for...

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Q: A random sample of 502 Vail Resorts’ guests were asked to rate

A random sample of 502 Vail Resorts’ guests were asked to rate their satisfaction on various attributes of their visit on a scale of 1–5 with 1 = very unsatisfied a...

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Q: A regression model to predict Y, the state burglary rate per

A regression model to predict Y, the state burglary rate per 100,000 people for 2005, used the following four state predictors: X1 = median age in 2005, X2 = number of 2005 bankruptcies, X3 = 2004 fed...

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Q: Which statement is not correct? Explain. a. The

Which statement is not correct? Explain. a. The sample data x1, x2, . . . , xn will be approximately normal if the sample size n is large. b. For a skewed population, the distribution of / is approxim...

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Q: A sample of 16 ATM transactions shows a mean transaction time of

A sample of 16 ATM transactions shows a mean transaction time of 67 seconds with a standard deviation of 12 seconds. (a). State the hypotheses to test whether the mean transaction time exceeds 60 se...

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Q: A sample of 9 customers in the “quick” lane in

A sample of 9 customers in the “quick” lane in a supermarket showed a mean purchase of $14.75 with a standard deviation of $2.10. (a) Find the 95 percent confidence interval for the true mean. (b) Why...

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Q: Which statement is false? Explain. a. To find

Which statement is false? Explain. a. To find probabilities in a continuous distribution, we add up the probabilities at each point. b. A uniform continuous model U(5,21) has mean 13 and standard devi...

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Q: Which statement is incorrect? Explain. a. If

Which statement is incorrect? Explain. a. If p = .50 and n = 100, the estimated standard error of the sample proportion is .05. b. In a sample size calculation for estimating π, it is conservative to...

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Q: Find the mean, standard deviation, and coefficient of variation for

Find the mean, standard deviation, and coefficient of variation for X = 5, 10, 20, 10, 15.

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Q: Five students in a large lecture class compared their scores on two

Five students in a large lecture class compared their scores on two exams. “Looks like the class mean was higher on the second exam,” Bob said. (a). What kind of...

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Q: A consulting firm used a random sample of 12 CIOs (chief

A consulting firm used a random sample of 12 CIOs (chief information officers) of large businesses to examine the relationship (if any) between salary (in thousands) and years of service in the firm....

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Q: Which of the following Excel formulas would be a correct way to

Which of the following Excel formulas would be a correct way to calculate P(X < 450) given that X is N(500, 60)? a. =NORM.DIST(450, 500, 60, 1) b. =NORM.S.DIST(450, 60) c. =1–NORM.DIST(450, 500, 60,...

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Q: In a random sample of 200 Colorado residents, 150 had skied

In a random sample of 200 Colorado residents, 150 had skied at least once last winter. A similar sample of 200 Utah residents revealed that 140 had skied at least once last winter. At α = .025, is the...

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Q: Which statement is correct concerning the normal approximation? Why not the

Which statement is correct concerning the normal approximation? Why not the others? a. The normal Poisson approximation is acceptable when λ > 10. b. The normal binomial approximation is better when n...

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Q: For the following contingency table, find (a) P (

For the following contingency table, find (a) P (H ∩ T); (b) P (S | G); (c) P(S)

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Q: Given n1 = 8, s1 = 14, n2 = 12

Given n1 = 8, s1 = 14, n2 = 12, s2 = 7. (a). Find the test statistic for a test for equal population variances. (b). At α = .05 in a two-tailed test, state the critical value and degrees of freedom....

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Q: Given H0: μ > 18 and H1: μ < 18

Given H0: μ > 18 and H1: μ < 18, we would commit Type I error if we a. conclude that μ > 18 when the truth is that μ < 18. b. conclude that μ < 18 when the truth is that μ > 18. c. fail to reject μ >...

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Q: The process that produces Sonora Bars (a type of candy)

The process that produces Sonora Bars (a type of candy) is intended to produce bars with a mean weight of 56 grams (g). The process standard deviation is known to be 0.77 g. A random sample of 49 cand...

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Q: (a) Plot the data on skier/snowboard visits.

(a) Plot the data on skier/snowboard visits. (b) Would a fitted trend be helpful? Explain. (c) Make a forecast for 2007–2008, using a trend model of your choice (or a judgment foreca...

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Q: For a multiple regression, which statement is false? Explain.

For a multiple regression, which statement is false? Explain. a. If R2 = .752 and R2 adj = .578, the model probably has at least one weak predictor. b. R2 adj can exceed R2 if the model contains some...

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Q: Which predictor coefficients differ significantly from zero at α = .05

Which predictor coefficients differ significantly from zero at α = .05? a. X3 and X5 b. X5 only c. all but X1 and X3

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Q: Which predictors differ significantly from zero at α = .05?

Which predictors differ significantly from zero at α = .05? a. X3 only b. X4 only c. both X3 and X4

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Q: In this regression with n = 40, which predictor differs significantly

In this regression with n = 40, which predictor differs significantly from zero at α = .01? a. X2 b. X3 c. X5

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Q: Which statement is incorrect? Explain. a. We

Which statement is incorrect? Explain. a. We need a Tukey test because ANOVA doesn’t tell which group means differ. b. Hartley’s test is needed to determine whether the means of the groups differ. c....

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Q: Given the following ANOVA table, find the F statistic and the

Given the following ANOVA table, find the F statistic and the critical value of F.05.

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Q: If P (A) = .30, P (B

If P (A) = .30, P (B) = .70, and P (A ∩ B) = .25, are A and B independent events? Explain.

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Q: Given the following ANOVA: / (a

Given the following ANOVA: (a). How many ATM locations were there? (b). What was the sample size? (c). At α = .05, is there a significant effect due to Day of Week? (d). At Î...

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Q: Given a sample correlation coefficient r = .373 with n =

Given a sample correlation coefficient r = .373 with n = 30, can you reject the hypothesis ρ = 0 for the population at α = .01? Explain, stating the critical value you are using in the test.

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Q: Which statement is incorrect? Explain. a. Correlation

Which statement is incorrect? Explain. a. Correlation uses a t-test with n - 2 degrees of freedom. b. Correlation analysis assumes that X is independent and Y is dependent. c. Correlation analysis is...

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Q: Based on the information in this ANOVA table, the coefficient of

Based on the information in this ANOVA table, the coefficient of determination R2 is a. 0.499 b. 0.501 c. 0.382

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Q: In a test of the regression model Y = β0 + β1X

In a test of the regression model Y = β0 + β1X with 27 observations, what is the critical value of t to test the hypothesis that β1 = 0 using α = .05 in a two-tailed test? a. 1.960 b. 2.060 c. 1.70...

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Q: For each of the following fitted trends, make a prediction for

For each of the following fitted trends, make a prediction for period t = 17: a. yt = 2286 e.076t b. yt = 1149 + 12.78t c. yt = 501 + 18.2t - 7.1t2

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Q: (a) Plot the data on leisure and hospitality employment.

(a) Plot the data on leisure and hospitality employment. (b) Describe the trend (if any) and discuss possible causes. (c) Fit the linear and exponential trends. Would these trend models give credible...

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Q: (a) Plot the data on lightning deaths. (b

(a) Plot the data on lightning deaths. (b) Describe the trend (if any) and discuss possible causes. (c) Fit an exponential trend to the data. Interpret the fitted equation. (d) Make a forecast for 201...

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Q: Define three quality metrics that might be used to describe quality and

Define three quality metrics that might be used to describe quality and performance in the following consumer products: (a) your personal vehicle (e.g., car, SUV, truck, bicycle, motorcycle); (b) the...

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Q: Bob said, “They must not be using quality control in

Bob said, “They must not be using quality control in automobile manufacturing. Just look at the J.D. Power data showing that new cars all seem to have defects.” (a) Discuss Bob’s assertion, focusing o...

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Q: Which statement is false? Explain. a. If

Which statement is false? Explain. a. If P(A) = .05, then the odds against event A’s occurrence are 19 to 1. b. If A and B are mutually exclusive events, then P (A ∪ B) = 0. c. The number of permutat...

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Q: Why are the control limits for an R chart asymmetric, while

Why are the control limits for an R chart asymmetric, while those of an  chart are symmetric?

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Q: Define (a) productivity, (b) quality control,

Define (a) productivity, (b) quality control, and (c) process control.

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Q: (a) Interpret the slope of the fitted regression Computer power

(a) Interpret the slope of the fitted regression Computer power dissipation = 15.73 + 0.032 Microprocessor speed, where Power dissipation is measured in watts and Microprocessor speed is measured in M...

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Q: A regression of accountants’ starting salaries in a large firm was estimated

A regression of accountants’ starting salaries in a large firm was estimated using 40 new hires and five predictors (college GPA, gender, score on CPA exam, years’ prior experience, size of graduating...

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Q: An agribusiness performed a regression of wheat yield (bushels per acre

An agribusiness performed a regression of wheat yield (bushels per acre) using observations on 25 test plots with four predictors (rainfall, fertilizer, soil acidity, hours of sun). The standard error...

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Q: A regression model to predict the price of a condominium for a

A regression model to predict the price of a condominium for a weekend getaway in a resort community included the following predictor variables: number of nights needed, number of bedrooms, whether th...

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Q: Refer back to the regression equation in exercise 12.12:

Refer back to the regression equation in exercise 12.12: NetIncome = 2,277 + .0307 Revenue. Recall that the variables are both in millions of dollars. (a) Calculate the residual for the x, y pair ($41...

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Q: The yield strength of a metal bolt has a mean of 6

The yield strength of a metal bolt has a mean of 6,050 pounds with a standard deviation of 100 pounds. Twenty samples of three bolts were tested, resulting in the means shown below. (a). Construct u...

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Q: Refer to the bolt strength problem 17.47. Assume μ

Refer to the bolt strength problem 17.47. Assume μ = 6,050 and σ = 100. Use the following 24 individual bolt strength observations to answer the questions posed. Problem 17...

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Q: In painting an automobile at the factory, the thickness of the

In painting an automobile at the factory, the thickness of the color coat has a process mean of 1.00 mil and a process standard deviation of 0.07 mil. Twenty samples of five cars were tested, resultin...

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Q: Concerning confidence intervals, which statement is most nearly correct? Why

Concerning confidence intervals, which statement is most nearly correct? Why not the others? a. We should use z instead of t when n is large. b. We use the Student’s t distribution when σ is unknown....

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Q: Refer to the paint thickness problem 17.49. Assume μ

Refer to the paint thickness problem 17.49. Assume μ = 1.00 and σ = 0.07. Use the following 35 individual observations on paint thickness to answer the questions posed. Pro...

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Q: Refer back to the regression equation in exercise 12.14:

Refer back to the regression equation in exercise 12.14: Credits = 15.4 - .07 Work. (a) Calculate the residual for the x, y pair (14, 18). Did the regression equation underestimate or overestimate the...

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Q: Refer to the freezer problem 17.51 with μ = 23

Refer to the freezer problem 17.51 with μ = 23 and σ = 2. Temperature measurements are recorded four times a day (at midnight, 0600, 1200, and 1800). Twenty samples of four ob...

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Q: Use MINITAB’s Stat > Basic Statistics > Normality Test or other software

Use MINITAB’s Stat > Basic Statistics > Normality Test or other software to obtain a probability plot for the Ashoka Curry House carry-out order data (see Exercise 15.16). Inte...

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Q: Set up control limits for an  chart, given  =

Set up control limits for an  chart, given  = 12.50,  = .42, and n = 5.

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Q: Set up control limits for an  chart, given μ =

Set up control limits for an  chart, given μ = 400, σ = 2, and n = 4.

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Q: Time (in seconds) to serve an early-morning customer

Time (in seconds) to serve an early-morning customer at a fast-food restaurant is normally distributed. Set up a control chart for the mean serving time, assuming that serving times were sampled in ra...

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Q: A study of the role of spreadsheets in planning in 55 small

A study of the role of spreadsheets in planning in 55 small firms defined Y = “satisfaction with sales growth” and X = “executive commitment to planning.” Analysis yielded an overall correlation of r...

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Q: Refer to the Wheat Chex box fill problem 17.56 with

Refer to the Wheat Chex box fill problem 17.56 with μ = 465 and σ = 3. Below are 30 individual observations on box fill. Problem 17.56: A box of Wheat Chex cereal is to be...

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Q: Regression analysis of free throws by 29 NBA teams during the 2002

Regression analysis of free throws by 29 NBA teams during the 2002–2003 season revealed the fitted regression Y = 55.2 + .73X (R2 = .874, syx = 53.2), where Y = total free throws made and X = total fr...

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Q: If the payoff of a risky investment has three possible outcomes ($

If the payoff of a risky investment has three possible outcomes ($1,000, $2,000, $5,000) with probabilities .60, .30, and .10 respectively, find the expected value. a. $1,500 b. $2,300 c. $1,700

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Q: Past experience indicates that the probability of a post-surgical complication

Past experience indicates that the probability of a post-surgical complication in a certain procedure is 6 percent. A hospital typically performs 200 such surgeries per month. (a). Find the control l...

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Q: A large retail toy store finds that, on average, a

A large retail toy store finds that, on average, a certain cheap (under $20) electronic toy has a = percent damage rate during shipping. From each incoming shipment, a sample of 100 is inspected. (...

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Q: Which abnormal pattern (cycle, instability, level shift, oscillation

Which abnormal pattern (cycle, instability, level shift, oscillation, trend, mixture), if any, exists in each of the charts shown above? If you see none, say so. If you see more than one possibility,...

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Q: Referring to Charts A–F, which Rules (1,

Referring to Charts A–F, which Rules (1, 2, 3, 4) are violated in each chart? Make a photocopy and circle the points that violate each rule.

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Q: Refer to the bolt strength problem 17.47. Assuming μ

Refer to the bolt strength problem 17.47. Assuming μ = 6,050 and σ = 100 with n = 3, then LCL = 5,876.8 and UCL 5 6,223.2. Below are five sets of 20 sample means using n = 3....

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Q: Refer to the paint problem 17.49 with μ = 1

Refer to the paint problem 17.49 with μ = 1.00 and σ = .07. With n = 5, LCL = .906 and UCL = 1.094. Below are five sets of 20 sample means using n = 5. Test each set of means...

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Q: Refer to the Wheat Chex problem 17.56 with μ =

Refer to the Wheat Chex problem 17.56 with μ = 465 and σ = 3. During production, samples of three boxes are weighed every 5 minutes. Problem 17.56: A box of Wheat Chex cer...

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Q: Each gum drop in two bags of Sathers Gum Drops was weighed

Each gum drop in two bags of Sathers Gum Drops was weighed (to the nearest .001 g) on a sensitive Mettler PE 360 Delta Range scale. After removing one outlier (to improve normality), there were 84 gum...

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Q: (a) Use Excel to make a scatter plot of the

(a) Use Excel to make a scatter plot of the data. (b) Select the data points, right-click, select Add Trendline, select the Options tab, and choose Display equation on chart and Display R-squared valu...

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Q: Below are recent financial ratios for a random sample of 20 integrated

Below are recent financial ratios for a random sample of 20 integrated health care systems. Operating Margin is total revenue minus total expenses divided by total revenue plus net operating profits....

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Q: Assuming independent arrivals with a mean of 2.5 arrivals per

Assuming independent arrivals with a mean of 2.5 arrivals per minute, find the probability that in a given minute there will be (a). exactly 2 arrivals; (b). at least 3 arrivals; (c). fewer than 4...

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Q: Consider the following data on 20 chemical reactions, with Y =

Consider the following data on 20 chemical reactions, with Y = chromatographic retention time (seconds) and X = molecular weight (gm/mole). (a) Make a scatter plot. (b) Use Excel to fit the regression...

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Q: Set up limits for the R chart, given  = 0

Set up limits for the R chart, given  = 0.82 and n = 6.

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Q: Set up limits for the R chart, given  = 12

Set up limits for the R chart, given  = 12 and n = 3.

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Q: For an  chart, what percent of sample means should be

For an  chart, what percent of sample means should be (a) within 1 sigma of the centerline; (b) within 2 sigmas of the centerline; (c) within 3 sigmas of the centerline; (d) outside 2 sigmas of the c...

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Q: Create control limits for a p chart for a process with π

Create control limits for a p chart for a process with π = .02 and subgroup size n = 500. Is it safe to assume normality? Explain.

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Q: Create control limits for a p chart for a process with π

Create control limits for a p chart for a process with π = .50 and subgroup size n = 20. Is it safe to assume normality? Explain.

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Q: Create control limits for a p chart for a process with π

Create control limits for a p chart for a process with π = .90 and subgroup size n = 40. Is it safe to assume normality? Explain.

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Q: Find the Cp and Cpk indexes for a process with μ =

Find the Cp and Cpk indexes for a process with μ = 720, σ = 1.0, LSL = 715, USL = 725. How would you rate the capability of this process? Explain.

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Q: Find the Cp and Cpk indexes for a process with μ =

Find the Cp and Cpk indexes for a process with μ = 0.426, σ = 0.001, LSL = 0.423, USL = 0.432. How would you rate the capability of this process? Explain.

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Q: Find the Cp and Cpk indexes for a process with μ =

Find the Cp and Cpk indexes for a process with μ = 55.4, σ = 0.1, LSL = 55.2, USL = 55.9. How would you rate the capability of this process? Explain.

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Q: Which is the correct z value for a two-tailed test

Which is the correct z value for a two-tailed test at α = .05? a. z = ±1.645 b. z = ±1.960 c. z = ±2.326

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Q: To print 8.5 × 5.5 note pads,

To print 8.5 × 5.5 note pads, a copy shop uses standard 8.5 × 11 paper, glues the long edge, then cuts the pads in half so that the pad width is 5.5 inches. However, there is...

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Q: An estimated regression for a random sample of observations on an assembly

An estimated regression for a random sample of observations on an assembly line is Defects = 3.2 + 0.045 Speed, where Defects is the number of defects per million parts and Speed is the number of unit...

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Q: (a) Interpret the slope of the fitted regression Sales =

(a) Interpret the slope of the fitted regression Sales = 842 - 37.5 Price. (b) If Price = 20, what is the prediction for Sales? (c) Would the intercept be meaningful if this regression represents DVD...

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Q: (a) Interpret the slope of the fitted regression CarTheft =

(a) Interpret the slope of the fitted regression CarTheft = 1,667 - 35.3 MedianAge, where CarTheft is the number of car thefts per 100,000 people by state, and MedianAge is the median age of the popul...

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Q: Which statement is correct concerning one-factor ANOVA? Why not

Which statement is correct concerning one-factor ANOVA? Why not the others? a. The ANOVA is a test to see whether the variances of c groups are the same. b. In ANOVA, the k groups are compared two at...

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Q: In a random experiment with 50 independent trials with constant probability of

In a random experiment with 50 independent trials with constant probability of success .30, find the mean and standard deviation of the number of successes.

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Q: Semiconductor lasers used in optical storage products require higher power levels forwrite

Semiconductor lasers used in optical storage products require higher power levels forwrite operations than for read operations. High-power-level operations lower the useful life of the laser. Lasers i...

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Q: A steel plate contains 20 bolts. Assume that 5 bolts are

A steel plate contains 20 bolts. Assume that 5 bolts are not torqued to the proper limit. Four bolts are selected at random, without replacement, to be checked for torque. a. What is the probability t...

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Q: If P(A | B) = 0.3,

If P(A | B) = 0.3, P(B) = 0.8, and P(A) = 0.3, are the events B and the complement of A independent?

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Q: If P(A) = 0.2, P(

If P(A) = 0.2, P(B) = 0.2, and A and B are mutually exclusive, are they independent?

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Q: A batch of 500 containers of frozen orange juice contains 5 that

A batch of 500 containers of frozen orange juice contains 5 that are defective. Two are selected, at random, without replacement, from the batch. Let A and B denote the events that the first and secon...

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Q: Disks of polycarbonate plastic from a supplier are analyzed for scratch and

Disks of polycarbonate plastic from a supplier are analyzed for scratch and shock resistance. The results from 100 disks are summarized as follows: Let A denote the event that a disk has high shock re...

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Q: Redundant array of inexpensive disks (RAID) is a technology that

Redundant array of inexpensive disks (RAID) is a technology that uses multiple hard drives to increase the speed of data transfer and provide instant data backup. Suppose that the probability of any h...

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Q: A test of a printed circuit board uses a random test pattern

A test of a printed circuit board uses a random test pattern with an array of 10 bits and each is equally likely to be 0 or 1. Assume the bits are independent. a. What is the probability that all bits...

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Q: The probability that a lab specimen contains high levels of contamination is

The probability that a lab specimen contains high levels of contamination is 0.10. Five samples are checked, and the samples are independent. a. What is the probability that none contain high levels o...

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Q: A player of a video game is confronted with a series of

A player of a video game is confronted with a series of four opponents and an 80% probability of defeating each opponent. Assume that the results from opponents are independent (and that when the play...

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Q: Eight cavities in an injection-molding tool produce plastic connectors that

Eight cavities in an injection-molding tool produce plastic connectors that fall into a common stream. A sample is chosen every several minutes. Assume that the samples are independent. a. What is the...

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Q: Customers are used to evaluate preliminary product designs. In the past

Customers are used to evaluate preliminary product designs. In the past, 95% of highly successful products received good reviews, 60% of moderately successful products received good reviews, and 10% o...

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Q: The British government has stepped up its information campaign regarding foot-

The British government has stepped up its information campaign regarding foot-and-mouth disease bymailing brochures to farmers around the country. It is estimated that 99% of Scottish farmers who rece...

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Q: Suppose that P(A | B) = 0.7

Suppose that P(A | B) = 0.7, P(A) = 0.5, and P(B) = 0.2. Determine P(B | A).

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Q: A new analytical method to detect pollutants in water is being tested

A new analytical method to detect pollutants in water is being tested. This new method of chemical analysis is important because, if adopted, it could be used to detect three different contaminants—or...

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Q: Disks of polycarbonate plastic from a supplier are analyzed for scratch and

Disks of polycarbonate plastic from a supplier are analyzed for scratch and shock resistance. The results from 100 disks are summarized here: Let A denote the event that a disk has high shock resistan...

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Q: In control replication, cells are replicated over a period of two

In control replication, cells are replicated over a period of two days. Two control mechanisms have been identified—one positive and one negative. Suppose that a replication is observed in three cells...

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Q: Samples of emissions from three suppliers are classified for conformance to air

Samples of emissions from three suppliers are classified for conformance to air-quality specifications. The results from 100 samples are summarized as follows: Let A denote the event that a sample is...

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Q: The rise time of a reactor is measured in minutes (and

The rise time of a reactor is measured in minutes (and fractions of minutes). Let the sample space be positive, real numbers. Define the events A and B as follows: A = {x | x < 72.5} and B = {x | x >...

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Q: The following table summarizes 204 endothermic reactions involving sodium bicarbonate.

The following table summarizes 204 endothermic reactions involving sodium bicarbonate. Let A denote the event that a reaction’s final temperature is 271 K or less. Let B denote the e...

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Q: A Web ad can be designed from four different colors, three

A Web ad can be designed from four different colors, three font types, five font sizes, three images, and five text phrases. How many different designs are possible?

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Q: Consider the hospital emergency department data in Example 2.6.

Consider the hospital emergency department data in Example 2.6. Let A denote the event that a visit is to hospital 1, and let B denote the event that a visit results in admittance to any hospital. Det...

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Q: The article “Term Efficacy of Ribavirin Plus Interferon Alfa in the

The article “Term Efficacy of Ribavirin Plus Interferon Alfa in the Treatment of Chronic Hepatitis C” [Gastroenterology (1996, Vol. 111(5), pp. 1307â€...

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Q: It is known that two defective cellular phones were erroneously sent to

It is known that two defective cellular phones were erroneously sent to a shipping lot that now has a total of 75 phones. A sample of phones will be selected from the lot without replacement. a. If th...

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Q: A computer system uses passwords that contain exactly eight characters, and

A computer system uses passwords that contain exactly eight characters, and each character is 1 of the 26 lowercase letters (a–z) or 26 uppercase letters (A–Z) or 10 integers (0–9). Let Ω denote the s...

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Q: Each of four transmitted bits is classified as either in error or

Each of four transmitted bits is classified as either in error or not in error.

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Q: The number of hits (views) is recorded at a high

The number of hits (views) is recorded at a high-volume Web site in a day.

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Q: In the final inspection of electronic power supplies, either units pass

In the final inspection of electronic power supplies, either units pass or three types of nonconformities might occur: functional, minor, or cosmetic. Three units are inspected.

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Q: An ammeter that displays three digits is used to measure current in

An ammeter that displays three digits is used to measure current in milliamperes.

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Q: The following two questions appear on an employee survey questionnaire. Each

The following two questions appear on an employee survey questionnaire. Each answer is chosen from the five-point scale 1 (never), 2, 3, 4, 5 (always). Is the corporation willing to listen to and fair...

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Q: Software to detect fraud in consumer phone cards tracks the number of

Software to detect fraud in consumer phone cards tracks the number of metropolitan areas where calls originate each day. It is found that 1% of the legitimate users originate calls from two or more me...

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Q: Consider the hospital emergency room data in Example 2.6.

Consider the hospital emergency room data in Example 2.6. Use Bayes’ theorem to calculate the probability that a person visits hospital 4 given they are LWBS. Data from Example 2.6:...

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Q: Suppose that a patient is selected randomly from those described in Exercise

Suppose that a patient is selected randomly from those described in Exercise 2.4.11. Let A denote the event that the patient is in group 1, and let B denote the event that there is no progression. Det...

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Q: Two Web colors are used for a site advertisement. If a

Two Web colors are used for a site advertisement. If a site visitor arrives from an affiliate, the probabilities of the blue or green colors being used in the advertisement are 0.8 and 0.2, respective...

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Q: An encryption–decryption system consists of three elements: encode,

An encryption–decryption system consists of three elements: encode, transmit, and decode. A faulty encode occurs in 0.5% of the messages processed, transmission errors occur in 1% of the messages, and...

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Q: A recreational equipment supplier finds that among orders that include tents,

A recreational equipment supplier finds that among orders that include tents, 40% also include sleeping mats. Only 5% of orders that do not include tents do include sleeping mats. Also, 20% of orders...

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Q: An e-mail filter is planned to separate valid e-

An e-mail filter is planned to separate valid e-mails from spam. The word free occurs in 60% of the spam messages and only 4% of the valid messages. Also, 20% of the messages are spam. Determine the f...

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Q: A credit card contains 16 digits. It also contains the month

A credit card contains 16 digits. It also contains the month and year of expiration. Suppose there are 1 million credit card holders with unique card numbers. A hacker randomly selects a 16-digit cred...

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Q: The following circuit operates if and only if there is a path

The following circuit operates if and only if there is a path of functional devices from left to right. The probability that each device functions is as shown. Assume that the probability that a devic...

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Q: The following circuit operates if and only if there is a path

The following circuit operates if and only if there is a path of functional devices from left to right. The probability that each device functions is as shown. Assume that the probability that a devic...

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Q: Consider the hospital emergency room data in Example 2.6.

Consider the hospital emergency room data in Example 2.6. Let A denote the event that a visit is to hospital 4, and let B denote the event that a visit results in LWBS (at any hospital). Are these eve...

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Q: A Web ad can be designed fromfour different colors, three font

A Web ad can be designed fromfour different colors, three font types, five font sizes, three images, and five text phrases. A specific design is randomly generated by the Web server when you visit the...

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Q: An integrated circuit contains 10 million logic gates (each can be

An integrated circuit contains 10 million logic gates (each can be a logical AND or OR circuit). Assume the probability of a gate failure is p and that the failures are independent. The integrated cir...

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Q: Table 2.1 provides data on wafers categorized by location and

Table 2.1 provides data on wafers categorized by location and contamination levels. Let A denote the event that contamination is low, and let B denote the event that the location is center. Are A and...

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Q: A computer system uses passwords that contain exactly eight characters, and

A computer system uses passwords that contain exactly eight characters, and each character is one of 26 lowercase letters (a–z) or 26 uppercase letters (A–Z) or 10 integers (0–9). Let Ω denote the set...

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Q: The following circuit operates if and only if there is a path

The following circuit operates if and only if there is a path of functional devices from left to right. Assume that devices fail independently and that the probability of failure of each device is as...

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Q: Decide whether a discrete or continuous random variable is the best model

Decide whether a discrete or continuous random variable is the best model for each of the following variables: a. The number of cracks exceeding one-half inch in 10miles of an interstate highway. b. T...

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Q: Decide whether a discrete or continuous random variable is the best model

Decide whether a discrete or continuous random variable is the best model for each of the following variables: a. The time until a projectile returns to earth. b. The number of times a transistor in a...

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Q: Decide whether a discrete or continuous random variable is the best model

Decide whether a discrete or continuous random variable is the best model for each of the following variables: a. The time for a computer algorithm to assign an image to a category. b. The number of b...

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Q: Samples of laboratory glass are in small, light packaging or heavy

Samples of laboratory glass are in small, light packaging or heavy, large packaging. Suppose that 2% and 1%, respectively, of the sample shipped in small and large packages, respectively, break during...

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Q: Samples of a cast aluminum part are classified on the basis of

Samples of a cast aluminum part are classified on the basis of surface finish (in microinches) and edge finish. The results of 100 parts are summarized as follows: Let A denote the event that a sampl...

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Q: A lot contains 15 castings from a local supplier and 25 castings

A lot contains 15 castings from a local supplier and 25 castings from a supplier in the next state. Two castings are selected randomly, without replacement, from the lot of 40. Let A be the event that...

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Q: If A, B, and C are mutually exclusive events,

If A, B, and C are mutually exclusive events, is it possible for P(A) = 0.3, P(B) = 0.4, and P(C) = 0.5? Why or why not?

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Q: Incoming calls to a customer service center are classified as complaints (

Incoming calls to a customer service center are classified as complaints (75% of calls) or requests for information (25% of calls). Of the complaints, 40% deal with computer equipment that does not re...

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Q: In the manufacturing of a chemical adhesive, 3% of all

In the manufacturing of a chemical adhesive, 3% of all batches have raw materials from two different lots. This occurs when holding tanks are replenished and the remaining portion of a lot is insuffic...

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Q: A robotic insertion tool contains 10 primary components. The probability that

A robotic insertion tool contains 10 primary components. The probability that any component fails during the warranty period is 0.01. Assume that the components fail independently and that the tool fa...

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Q: A machine tool is idle 15% of the time. You

A machine tool is idle 15% of the time. You request immediate use of the tool on five different occasions during the year. Assume that your requests represent independent events. a. What is the probab...

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Q: A company that tracks the use of its Web site determined that

A company that tracks the use of its Web site determined that the more pages a visitor views, the more likely the visitor is to request more information (RMI). Use the following table to answer the qu...

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Q: An article in Genome Research [“An Assessment of Gene Prediction Accuracy

An article in Genome Research [“An Assessment of Gene Prediction Accuracy in Large DNA Sequences” (2000, Vol. 10, pp. 1631–1642)] considered the a...

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Q: A batch contains 36 bacteria cells. Assume that 12 of the

A batch contains 36 bacteria cells. Assume that 12 of the cells are not capable of cellular replication. Of the cells, 6 are selected at random, without replacement, to be checked for replication. a....

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Q: A congested computer network has a 0.002 probability of losing

A congested computer network has a 0.002 probability of losing a data packet, and packet losses are independent events. A lost packet must be resent. a. What is the probability that an e-mail message...

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Q: Consider the treatments in Exercise 2.1.25. Suppose

Consider the treatments in Exercise 2.1.25. Suppose a patient is selected randomly. Let A denote the event that the patient is treated with ribavirin plus interferon alfa or interferon alfa, and let B...

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Q: The time until a service transaction is requested of a computer to

The time until a service transaction is requested of a computer to the nearest millisecond.

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Q: The pH reading of a water sample to the nearest tenth of

The pH reading of a water sample to the nearest tenth of a unit.

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Q: The voids in a ferrite slab are classified as small, medium

The voids in a ferrite slab are classified as small, medium, or large. The number of voids in each category is measured by an optical inspection of a sample.

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Q: A sampled injection-molded part could have been produced in either

A sampled injection-molded part could have been produced in either one of two presses and in any one of the eight cavities in each press.

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Q: An order for an automobile can specify either an automatic or a

An order for an automobile can specify either an automatic or a standard transmission, either with or without air conditioning, and with any one of the four colors red, blue, black, or white. Describe...

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Q: Calls are repeatedly placed to a busy phone line until a connection

Calls are repeatedly placed to a busy phone line until a connection is achieved.

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Q: Three attempts are made to read data in a magnetic storage device

Three attempts are made to read data in a magnetic storage device before an error recovery procedure is used. The error recovery procedure attempts three corrections before an “abort” message is sent...

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Q: An electronic storage device uses an error recovery procedure that requires an

An electronic storage device uses an error recovery procedure that requires an immediate satisfactory readback of any written data. If the readback is not successful after three writing operations, th...

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Q: Three events are shown on the Venn diagram in the following figure

Three events are shown on the Venn diagram in the following figure: Reproduce the figure and shade the region that corresponds to each of the following events. a. A′ b. A â&#...

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Q: In an injection-molding operation, the length and width,

In an injection-molding operation, the length and width, denoted as X and Y, respectively, of each molded part are evaluated. Let A denote the event of 48 < X < 52 centimeters B denote the event of 9...

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Q: A digital scale that provides weights to the nearest gram is used

A digital scale that provides weights to the nearest gram is used. a. What is the sample space for this experiment? Let A denote the event that a weight exceeds 11 grams, let B denote the event that a...

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Q: In light-dependent photosynthesis, light quality refers to the wavelengths

In light-dependent photosynthesis, light quality refers to the wavelengths of light that are important. The wavelength of a sample of photosynthetically active radiations (PAR) is measured to the near...

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Q: Four bits are transmitted over a digital communications channel. Each bit

Four bits are transmitted over a digital communications channel. Each bit is either distorted or received without distortion. Let Ai denote the event that the ith bit is distorted, i = 1,…, 4. a. Desc...

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Q: A sample of two printed circuit boards is selected without replacement from

A sample of two printed circuit boards is selected without replacement from a batch. Describe the (ordered) sample space for each of the following batches: a. The batch contains 90 boards that are not...

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Q: A sample of two items is selected without replacement from a batch

A sample of two items is selected without replacement from a batch. Describe the (ordered) sample space for each of the following batches: a. The batch contains the items {a, b, c, d}. b. The batch co...

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Q: A wireless garage door opener has a code determined by the up

A wireless garage door opener has a code determined by the up or down setting of 12 switches. How many outcomes are in the sample space of possible codes?

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Q: In a manufacturing operation, a part is produced by machining,

In a manufacturing operation, a part is produced by machining, polishing, and painting. If there are three machine tools, four polishing tools, and three painting tools, how many different routings (c...

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Q: New designs for a wastewater treatment tank have proposed three possible shapes

New designs for a wastewater treatment tank have proposed three possible shapes, four possible sizes, three locations for input valves, and four locations for output valves. How many different product...

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Q: Energy released from cells breaks the molecular bond and converts ATP (

Energy released from cells breaks the molecular bond and converts ATP (adenosine triphosphate) into ADP (adenosine diphosphate). Storage of ATP in muscle cells (even for an athlete) can sustain maxima...

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Q: A manufacturing process consists of 10 operations that can be completed in

A manufacturing process consists of 10 operations that can be completed in any order. How many different production sequences are possible?

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Q: Abatch of 140 semiconductor chips is inspected by choosing a sample of

Abatch of 140 semiconductor chips is inspected by choosing a sample of 5 chips without replacement. Assume 10 of the chips do not conform to customer requirements. a. How many different samples are po...

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Q: In a sheet metal operation, three notches and four bends are

In a sheet metal operation, three notches and four bends are required. If the operations can be done in any order, how many different ways of completing the manufacturing are possible?

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Q: In the laboratory analysis of samples from a chemical process, five

In the laboratory analysis of samples from a chemical process, five samples from the process are analyzed daily. In addition, a control sample is analyzed twice each day to check the calibration of th...

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Q: In the layout of a printed circuit board for an electronic product

In the layout of a printed circuit board for an electronic product, 12 different locations can accommodate chips. a. If five different types of chips are to be placed on the board, how many different...

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Q: Consider the design of a communication system. a. How

Consider the design of a communication system. a. How many three-digit phone prefixes that are used to represent a particular geographic area (such as an area code) can be created from the digits 0 th...

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Q: In the design of an electromechanical product, 12 components are to

In the design of an electromechanical product, 12 components are to be stacked into a cylindrical casing in a manner that minimizes the impact of shocks. One end of the casing is designated as the bot...

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Q: A bin of 50 parts contains 5 that are defective. A

A bin of 50 parts contains 5 that are defective. A sample of 10 parts is selected without replacement. How many samples contain at least 4 defective parts?

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Q: Plastic parts produced by an injection-molding operation are checked for

Plastic parts produced by an injection-molding operation are checked for conformance to specifications. Each tool contains 12 cavities in which parts are produced, and these parts fall into a conveyor...

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Q: Similar to the hospital schedule in Example 2.9, suppose

Similar to the hospital schedule in Example 2.9, suppose that an operating room needs to handle three knee, four hip, and five shoulder surgeries. a. How many different sequences are possible? b. How...

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Q: The probability that a customer’s order is not shipped on time is

The probability that a customer’s order is not shipped on time is 0.05. A particular customer places three orders, and the orders are placed far enough apart in time that they can be considered to be...

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Q: The sample space of a random experiment is {a, b

The sample space of a random experiment is {a, b, c, d, e} with probabilities 0.1, 0.1, 0.2, 0.4, and 0.2, respectively. Let A denote the event {a, b, c}, and let B denote the event {c, d, e}. Determi...

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Q: A part selected for testing is equally likely to have been produced

A part selected for testing is equally likely to have been produced on any one of six cutting tools. a. What is the sample space? b. What is the probability that the part is from tool 1? c. What is th...

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Q: An injection-molded part is equally likely to be obtained from

An injection-molded part is equally likely to be obtained from any one of the eight cavities on a mold. a. What is the sample space? b. What is the probability that a part is from cavity 1 or 2? c. Wh...

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Q: A credit card contains 16 digits between 0 and 9. However

A credit card contains 16 digits between 0 and 9. However, only 100 million numbers are valid. If a number is entered randomly, what is the probability that it is a valid number?

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Q: In a NiCd battery, a fully charged cell is composed of

In a NiCd battery, a fully charged cell is composed of nickelic hydroxide. Nickel is an element that has multiple oxidation states and that is usually found in the following states: a. What is the pro...

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Q: A message can follow different paths through servers on a network.

A message can follow different paths through servers on a network. The sender’s message can go to one of five servers for the first step; each of them can send to five servers at the second step; each...

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Q: Suppose your vehicle is licensed in a state that issues license plates

Suppose your vehicle is licensed in a state that issues license plates that consist of three digits (between 0 and 9) followed by three letters (between A and Z). If a license number is selected rando...

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Q: Disks of polycarbonate plastic from a supplier are analyzed for scratch and

Disks of polycarbonate plastic from a supplier are analyzed for scratch and shock resistance. The results from 100 disks are summarized as follows: Let A denote the event that a disk has high shock r...

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Q: Magnesium alkyls are used as homogenous catalysts in the production of linear

Magnesium alkyls are used as homogenous catalysts in the production of linear low-density polyethylene (LLDPE), which requires a finer magnesium powder to sustain a reaction. Redox reaction experiment...

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Q: An article in the Journal of Database Management [“Experimental Study of

An article in the Journal of Database Management [“Experimental Study of a Self-Tuning Algorithm for DBMS Buffer Pools” (2005, Vol. 16, pp. 1–20)]...

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Q: In circuit testing of printed circuit boards, each board either fails

In circuit testing of printed circuit boards, each board either fails or does not fail the test. A board that fails the test is then checked further to determine which one of five defect types is the...

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Q: Samples of emissions from three suppliers are classified for conformance to air

Samples of emissions from three suppliers are classified for conformance to air-quality specifications. The results from 100 samples are summarized as follows: Let A denote the event that a sample is...

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Q: If A, B, and C are mutually exclusive events with

If A, B, and C are mutually exclusive events with P(A) = 0.2, P(B) = 0.3, and P(C) = 0.4, determine the following probabilities: a. P(A ∪ B ∪ C) b. P(A ∩ B ∩ C) c. P(A ∩ B) d. P[(A ∪ B) ∩ C] e. P(A′...

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Q: If P(A) = 0.3, P(

If P(A) = 0.3, P(B) = 0.2, and P(A ∩ B) = 0.1, determine the following probabilities: a. P(A′) b. P(A ∪ B) c. P(A′ ∩ B) d. P(A ∩ B′) e. P[(A ∪ B)′] f. P(A′ ∪ B)

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Q: A manufacturer of front lights for automobiles tests lamps under a high

A manufacturer of front lights for automobiles tests lamps under a high-humidity, high-temperature environment using intensity and useful life as the responses of interest. The following table shows t...

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Q: In the article “ACL Reconstruction Using Bone-Patellar Tendon-

In the article “ACL Reconstruction Using Bone-Patellar Tendon-Bone Press-Fit Fixation: 10-Year Clinical Results” in Knee Surgery, Sports Traumatology, Arthroscopy (...

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Q: Consider the hospital emergency room data in Example 2.6.

Consider the hospital emergency room data in Example 2.6. Let A denote the event that a visit is to hospital 4, and let B denote the event that a visit results in LWBS (at any hospital). Use the addi...

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Q: Strands of copper wire from a manufacturer are analyzed for strength and

Strands of copper wire from a manufacturer are analyzed for strength and conductivity. The results from 100 strands are as follows: a. If a strand is randomly selected, what is the probability that it...

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Q: A computer system uses passwords that are six characters, and each

A computer system uses passwords that are six characters, and each character is one of the 26 letters (a–z) or 10 integers (0–9). Uppercase letters are not used. Let A denote the event that a password...

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Q: A Web ad can be designed from four different colors, three

A Web ad can be designed from four different colors, three font types, five font sizes, three images, and five text phrases. A specific design is randomly generated by the Web server when you visit th...

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Q: A computer system uses passwords that contain exactly eight characters, and

A computer system uses passwords that contain exactly eight characters, and each character is one of the 26 lowercase letters (a–z) or 26 uppercase letters (A–Z) or 10 integers (0–9). Assume all passw...

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Q: Transactions to a computer database are either new items or changes to

Transactions to a computer database are either new items or changes to previous items. The addition of an item can be completed in less than 100 milliseconds 90% of the time, but only 20% of changes t...

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Q: Consider the three patient groups in Exercise 2.1.25

Consider the three patient groups in Exercise 2.1.25. Let A denote the event that the patient was treated with ribavirin plus interferon alfa, and let B denote the event that the response was complete...

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Q: The article “Clinical and Radiographic Outcomes of Four Different Treatment Strategies

The article “Clinical and Radiographic Outcomes of Four Different Treatment Strategies in Patients with Early Rheumatoid Arthritis” [Arthritis & Rheumatism (2005, Vol. 52, pp. 3381–3390)] considered f...

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Q: The analysis of results from a leaf transmutation experiment (turning a

The analysis of results from a leaf transmutation experiment (turning a leaf into a petal) is summarized by type of transformation completed: a. If a leaf completes the color transformation, what is t...

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Q: Samples of skin experiencing desquamation are analyzed for both moisture and melanin

Samples of skin experiencing desquamation are analyzed for both moisture and melanin content. The results from 100 skin samples are as follows: Let A denote the event that a sample has low melanin con...

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Q: The following table summarizes the number of deceased beetles under autolysis (

The following table summarizes the number of deceased beetles under autolysis (the destruction of a cell after its death by the action of its own enzymes) and putrefaction (decomposition of organic ma...

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Q: A maintenance firm has gathered the following information regarding the failure mechanisms

A maintenance firm has gathered the following information regarding the failure mechanisms for air conditioning systems: The units without evidence of gas leaks or electrical failure showed other type...

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Q: Consider the endothermic reactions in Exercise 2.1.22.

Consider the endothermic reactions in Exercise 2.1.22. Let A denote the event that a reaction’s final temperature is 271 K or less. Let B denote the event that the heat absorbed is above target. Deter...

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Q: A batch of 500 containers for frozen orange juice contains 5 that

A batch of 500 containers for frozen orange juice contains 5 that are defective. Three are selected, at random, without replacement from the batch. a. What is the probability that the second one selec...

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Q: Suppose A and B are mutually exclusive events. Construct a Venn

Suppose A and B are mutually exclusive events. Construct a Venn diagram that contains the three events A, B, and C such that P(A | C) = 1 and P(B | C) = 0.

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Q: An article in The Canadian Entomologist (Harcourt et al., 1977

An article in The Canadian Entomologist (Harcourt et al., 1977, Vol. 109, pp. 1521–1534) reported on the life of the alfalfa weevil from eggs to adulthood. The following table shows...

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Q: Let E1, E2, and E3 denote the samples that conform

Let E1, E2, and E3 denote the samples that conform to a percentage of solids specification, a molecular weight specification, and a color specification, respectively.Atotal of 240 samples are classifi...

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Q: Consider the hospital emergency room data in Example 2.6.

Consider the hospital emergency room data in Example 2.6. Let A denote the event that a visit is to hospital 4, and let B denote the event that a visit results in LWBS (at any hospital). Determine the...

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Q: A computer system uses passwords that contain exactly eight characters, and

A computer system uses passwords that contain exactly eight characters, and each character is one of the 26 lowercase letters (a–z) or 26 uppercase letters (A–Z) or 10 integers (0–9). Let Ω denote the...

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Q: Suppose that a patient is selected randomly from those described in Exercise

Suppose that a patient is selected randomly from those described in Exercise 2.4.11. Let A denote the event that the patient is in group 1, and let B denote the event that there is no progression. Det...

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Q: Consider the hospital emergency room data in Example 2.6.

Consider the hospital emergency room data in Example 2.6. Let A denote the event that a visit is to hospital 4, and let B denote the event that a visit results in LWBS(at any hospital). Determine the...

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Q: Suppose that P(A | B) = 0.4

Suppose that P(A | B) = 0.4 and P(B) = 0.5. Determine the following: a. P(A ∩ B) b. P(A′ ∩ B)

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Q: Suppose that P(A | B) = 0.2

Suppose that P(A | B) = 0.2, P(A | B′) = 0.3, and P(B) = 0.8. What is P(A)?

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Q: The probability is 1% that an electrical connector that is kept

The probability is 1% that an electrical connector that is kept dry fails during the warranty period. If the connector is ever wet, the probability of a failure during the warranty period is 5%. If 90...

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Q: Heart failures are due to either natural occurrences (87%) or

Heart failures are due to either natural occurrences (87%) or outside factors (13%). Outside factors are related to induced substances (73%) or foreign objects (27%). Natural occurrences are caused by...

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Q: The edge roughness of slit paper products increases as knife blades wear

The edge roughness of slit paper products increases as knife blades wear. Only 1% of products slit with new blades have rough edges, 3% of products slit with blades of average sharpness exhibit roughn...

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Q: A lot of 100 semiconductor chips contains 20 that are defective.

A lot of 100 semiconductor chips contains 20 that are defective. a. Two are selected, at random, without replacement, from the lot. Determine the probability that the second chip selected is defective...

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Q: The following circuit operates if and only if there is a path

The following circuit operates if and only if there is a path of functional devices from left to right. Assume devices fail independently and that the probability of failure of each device is as shown...

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Q: Computer keyboard failures are due to faulty electrical connects (12%)

Computer keyboard failures are due to faulty electrical connects (12%) or mechanical defects (88%). Mechanical defects are related to loose keys (27%) or improper assembly (73%). Electrical connect de...

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Q: An article in the British Medical Journal [“Comparison of Treatment of

An article in the British Medical Journal [“Comparison of Treatment of Renal Calculi by Operative Surgery, Percutaneous Nephrolithotomy, and Extracorporeal Shock Wave Lithotripsy” (1986, Vol. 82, pp....

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Q: Consider the hospital emergency room data in Example 2.6.

Consider the hospital emergency room data in Example 2.6. Let A denote the event that a visit is to hospital 4 and let B denote the event that a visit results in LWBS (at any hospital). Data from Exa...

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Q: Suppose that a patient is selected randomly from those described in Exercise

Suppose that a patient is selected randomly from those described in Exercise 2.4.11. Let A denote the event that the patient is in group 1, and let B denote the event for which there is no progression...

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Q: AWeb ad can be designed fromfour different colors, three font types

AWeb ad can be designed fromfour different colors, three font types, five font sizes, three images, and five text phrases. A specific design is randomly generated by the Web server when you visit the...

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Q: Similar to the hospital schedule in Example 2.9, suppose

Similar to the hospital schedule in Example 2.9, suppose that an operating room needs to schedule three knee, four hip, and five shoulder surgeries. Assume that all schedules are equally likely. Deter...

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Q: Use the axioms of probability to show the following: a

Use the axioms of probability to show the following: a. For any event E, P(E′) = 1 − P(E). b. P(Ø) = 0 c. If A is contained in B, then P(A) ≤ P(B). Answer: (a) Because E and E' are mutually exclusiv...

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Q: Suppose that a patient is selected randomly from those described in Exercise

Suppose that a patient is selected randomly from those described in Exercise 2.1.25. Let A denote the event that the patient is in the group treated with interferon alfa, and let B denote the event th...

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Q: A Web ad can be designed from four different colors, three

A Web ad can be designed from four different colors, three font types, five font sizes, three images, and five text phrases. A specific design is randomly generated by the Web server when you visit th...

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Q: Similar to the hospital schedule in Example 2.9, suppose

Similar to the hospital schedule in Example 2.9, suppose that an operating room needs to schedule three knee, four hip, and five shoulder surgeries. Assume that all schedules are equally likely. Deter...

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Q: Suppose that X has a Poisson distribution. Determine the following probabilities

Suppose that X has a Poisson distribution. Determine the following probabilities when the mean of X is 4 and repeat for a mean of 0.4: a. P(X = 0) b. P(X ≤ 2) c. P(X = 4) d. P(X = 8)

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Q: Inclusions are defects in poured metal caused by contaminants. The number

Inclusions are defects in poured metal caused by contaminants. The number of (large) inclusions in cast iron follows a Poisson distribution with a mean of 2.5 per cubic millimeter. Determine the follo...

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Q: A batch of 500 machined parts contains 10 that do not conform

A batch of 500 machined parts contains 10 that do not conform to customer requirements. The random variable is the number of parts in a sample of five parts that do not conform to customer requirement...

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Q: A batch of 500 machined parts contains 10 that do not conform

A batch of 500 machined parts contains 10 that do not conform to customer requirements. Parts are selected successively, without replacement, until a nonconforming part is obtained. The random variabl...

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Q: The random variable is the number of computer clock cycles required to

The random variable is the number of computer clock cycles required to complete a selected arithmetic calculation.

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Q: The random variable is the number of surface flaws in a large

The random variable is the number of surface flaws in a large coil of galvanized steel.

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Q: A group of 10,000 people are tested for a gene

A group of 10,000 people are tested for a gene called Ifi202 that has been found to increase the risk for lupus. The random variable is the number of people who carry the gene.

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Q: The number of mutations in a nucleotide sequence of length 40,

The number of mutations in a nucleotide sequence of length 40,000 in a DNA strand after exposure to radiation is measured. Each nucleotide may be mutated.

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Q: A healthcare provider schedules 30 minutes for each patient’s visit, but

A healthcare provider schedules 30 minutes for each patient’s visit, but some visits require extra time. The random variable is the number of patients treated in an eight-hour day.

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Q: Determine the cumulative distribution function for the random variable in Exercise 3

Determine the cumulative distribution function for the random variable in Exercise 3.1.9.

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Q: Determine the cumulative distribution function of the random variable in Exercise 3

Determine the cumulative distribution function of the random variable in Exercise 3.1.10.

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Q: Determine the cumulative distribution function for the random variable in Exercise 3

Determine the cumulative distribution function for the random variable in Exercise 3.1.11.

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Q: Cabs pass your workplace according to a Poisson process with a mean

Cabs pass your workplace according to a Poisson process with a mean of five cabs per hour. Suppose that you exit the workplace at 6:00 P.M. Determine the following: a. Probability that you wait more t...

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Q: Determine the cumulative distribution function for the random variable in Exercise 3

Determine the cumulative distribution function for the random variable in Exercise 3.1.12; also determine the following probabilities: a. P(X < 1.5) b. P(X ≤ 3) c. P(X > 2) d. P(1 < X ≤ 2)

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Q: Determine the cumulative distribution function for the random variable in Exercise 3

Determine the cumulative distribution function for the random variable in Exercise 3.1.13.

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Q: Determine the cumulative distribution function for the random variable in Exercise 3

Determine the cumulative distribution function for the random variable in Exercise 3.1.16.

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Q: / a. P(X ≤ 3) b

a. P(X ≤ 3) b. P(X ≤ 2) c. P(1 ≤ X ≤ 2) d. P(X > 2)

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Q: / a. P(X ≤ 50) b

a. P(X ≤ 50) b. P(X ≤ 40) c. P(40 ≤ X ≤ 60) d. P(X e. P(0 ≤ X f. P(−10

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Q: If the range of X is the set {0, 1

If the range of X is the set {0, 1, 2, 3, 4} and P(X = x) = 0.2, determine the mean and variance of the random variable.

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Q: Consider the time to recharge the flash in cell-phone cameras

Consider the time to recharge the flash in cell-phone cameras as in Example 3.1. Assume that the probability that a camera passes the test is 0.8 and the cameras perform independently. Determine the f...

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Q: Customers visit aWeb site, and the probability of an order if

Customers visit aWeb site, and the probability of an order if a customer views five or fewer pages is 0.01. However, if a customer views more than five pages, the probability of an order is 0.1. The p...

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Q: An array of 30 LED bulbs is used in an automotive light

An array of 30 LED bulbs is used in an automotive light. The probability that a bulb is defective is 0.001 and defective bulbs occur independently. Determine the following: a. Probability that an auto...

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Q: The probability that a visitor to aWeb site provides contact data for

The probability that a visitor to aWeb site provides contact data for additional information is 0.01. Assume that 1000 visitors to the site behave independently. Determine the following probabilities:...

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Q: The article “An Association Between Fine Particles and Asthma Emergency Department

The article “An Association Between Fine Particles and Asthma Emergency Department Visits for Children in Seattle” [Environmental Health Perspectives June 1999, Vol. 107(6)] used Poisson models for th...

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Q: Consider the time to recharge the flash in cell-phone cameras

Consider the time to recharge the flash in cell-phone cameras as in Example 3.1. Assume that the probability that a camera passes the test is 0.8 and the cameras perform independently. What is the sma...

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Q: Let the random variable X be equally likely to assume any of

Let the random variable X be equally likely to assume any of the values 1/8, 1/4, or 3/8. Determine the mean and variance of X.

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Q: Let X denote the number of bits received in error in a

Let X denote the number of bits received in error in a digital communication channel, and assume that X is a binomial random variable with p = 0.001. If 1000 bits are transmitted, determine the follow...

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Q: An automated egg carton loader has a 1% probability of cracking

An automated egg carton loader has a 1% probability of cracking an egg, and a customer will complain if more than one egg per dozen is cracked. Assume that each egg load is an independent event. a. Wh...

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Q: A congested computer network has a 1%chance of losing a

A congested computer network has a 1%chance of losing a data packet that must be resent, and packet losses are independent events. An e-mail message requires 100 packets. a. What is the distribution o...

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Q: A particularly long traffic light on your morning commute is green on

A particularly long traffic light on your morning commute is green on 20% of the mornings. Assume that each morning represents an independent trial. a. What is the probability that the first morning t...

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Q: The probability that an eagle kills a rabbit in a day of

The probability that an eagle kills a rabbit in a day of hunting is 10%. Assume that results are independent for each day. a. What is the distribution of the number of days until a successful hunt? b...

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Q: An electronic scale in an automated filling operation stops themanufacturing line after

An electronic scale in an automated filling operation stops themanufacturing line after three underweight packages are detected. Suppose that the probability of an underweight package is 0.001 and eac...

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Q: The number of telephone calls that arrive at a phone exchange is

The number of telephone calls that arrive at a phone exchange is often modeled as a Poisson random variable. Assume that on the average there are 10 calls per hour. Determine the following probabiliti...

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Q: A shipment of chemicals arrives in 15 totes. Three of the

A shipment of chemicals arrives in 15 totes. Three of the totes are selected at random without replacement for an inspection of purity. If two of the totes do not conform to purity requirements, what...

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Q: Traffic flow is traditionally modeled as a Poisson distribution. A traffic

Traffic flow is traditionally modeled as a Poisson distribution. A traffic engineer monitors the traffic flowing through an intersection with an average of six cars per minute. To set the timing of a...

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The number of messages that arrive at aWeb site is a Poisson random variable with a mean of five messages per hour. a. What is the probability that five messages are received in 1.0 hour? b. What is t...

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Q: The number of errors in a textbook follows a Poisson distribution with

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The probability that an individual recovers from an illness in a one-week time period without treatment is 0.1. Suppose that 20 independent individuals suffering from this illness are treated with a d...

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In a manufacturing process that laminates several ceramic layers, 1% of the assemblies are defective. Assume that the assemblies are independent. a. What is the mean number of assemblies that need to...

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Q: A manufacturer of a consumer electronics product expects 2% of units

A manufacturer of a consumer electronics product expects 2% of units to fail during the warranty period. A sample of 500 independent units is tracked for warranty performance. a. What is the probabili...

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Q: Determine the probability mass function for the random variable with the following

Determine the probability mass function for the random variable with the following cumulative distribution function:

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Q: Suppose that the number of customers who enter a store in an

Suppose that the number of customers who enter a store in an hour is a Poisson random variable, and suppose that P(X = 0) = 0.05. Determine the mean and variance of X.

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Q: The random variable X has the following probability distribution: /

The random variable X has the following probability distribution: Determine the following: a. P(X ≤ 3) b. P(X > 2.5) c. P(2.7 d. E(X) e. V(X)

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Q: Assume that the number of errors along a magnetic recording surface is

Assume that the number of errors along a magnetic recording surface is a Poisson random variable with amean of one error every 105 bits. A sector of data consists of 4096 eight-bit bytes. a. What is t...

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Each main bearing cap in an engine contains 4 bolts. The bolts are selected at random without replacement froma parts bin that contains 30 bolts from one supplier and 70 bolts from another. a. What is...

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From 500 customers, a major appliance manufacturer randomly selects a sample without replacement. The company estimates that 25% of the customers will reply to the survey. If this estimate is correct,...

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An installation technician for a specialized communication system is dispatched to a city only when three or more orders have been placed. Suppose that orders follow a Poisson distribution with a mean...

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Saguaro cacti are large cacti indigenous to the southwesternUnited States and Mexico.Assume that the number of saguaro cacti in a region follows a Poisson distribution with a mean of 280 per square ki...

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Q: Determine the mean and variance of the random variable in Exercise 3

Determine the mean and variance of the random variable in Exercise 3.1.10.

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Q: Determine the mean and variance of the random variable in Exercise 3

Determine the mean and variance of the random variable in Exercise 3.1.11.

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Q: Determine the mean and variance of the random variable in Exercise 3

Determine the mean and variance of the random variable in Exercise 3.1.12.

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Data from www.centralhudsonlabs.com determined the mean number of insect fragments in 225-gram chocolate bars was 14.4, but three brands had insect contamination more than twice the average. See the U...

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Q: Determine the mean and variance of the random variable in Exercise 3

Determine the mean and variance of the random variable in Exercise 3.1.13.

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In a NiCd battery, a fully charged cell is composed of nickelic hydroxide. Nickel is an element that has multiple oxidation states. Assume the following proportions of the states: a. Determine the cum...

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Q: f (x) = (8∕7)(1∕

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Q: f (x) = 2x + 1 25 , x =

f (x) = 2x + 1 25 , x = 0, 1, 2, 3, 4 a. P(X = 4) b. P(X ≤ 1) c. P(2 ≤ X < 4) d. P(X > −10)

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Q: Consider the hospital patients in Example 2.6. Two patients

Consider the hospital patients in Example 2.6. Two patients are selected randomly, with replacement, from the total patients at Hospital 1. What is the probability mass function of the number of patie...

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Q: / a. P(X ≥ 2) b

a. P(X ≥ 2) b. P(X c. P(X = 1.5) d. P(X 2.1)

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Q: An article in Knee Surgery, Sports Traumatology, Arthroscopy [“Arthroscopic

An article in Knee Surgery, Sports Traumatology, Arthroscopy [“Arthroscopic Meniscal Repair with an Absorbable Screw: Results and Surgical Technique” (2005, Vol. 13, pp. 273–279)] cited a success rate...

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Q: Marketing estimates that a new instrument for the analysis of soil samples

Marketing estimates that a new instrument for the analysis of soil samples will be very successful, moderately successful, or unsuccessful with probabilities 0.3, 0.6, and 0.1, respectively. The yearl...

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Q: Astronomers treat the number of stars in a given volume of space

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Q: An assembly consists of threemechanical components. Suppose that the probabilities that

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Q: Let the random variable X have a discrete uniform distribution on the

Let the random variable X have a discrete uniform distribution on the integers 0 ≤ x ≤ 99. Determine the mean and variance of X.

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Q: Suppose that 1000 seven-digit telephone numbers within your area code

Suppose that 1000 seven-digit telephone numbers within your area code are dialed randomly. What is the probability that your number is called?

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Q: Each multiple-choice question on an examhas four choices. Suppose

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Q: Trees are subjected to different levels of carbon dioxide atmosphere with 6

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Q: For each scenario (a)–(j), state whether or not

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Q: The number of cracks in a section of interstate highway that are

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Q: Let X be a binomial random variable with p = 0.

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Q: The random variable X has a binomial distribution with n = 10

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Q: Determine the cumulative distribution function of a binomial random variable with n

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Q: Heart failure is due to either natural occurrences (87%) or

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Q: A computer system uses passwords that are exactly six characters and each

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Q: Samples of 20 parts from a metal punching process are selected every

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Q: Because all airline passengers do not show up for their reserved seat

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Q: Consider the lengths of stay at a hospital’s emergency department in Exercise

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Q: Suppose that the random variable X has a geometric distribution with p

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Q: In a clinical study, volunteers are tested for a gene that

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Q: Assume that each of your calls to a popular radio station has

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Q: Heart failure is due to either natural occurrences (87%) or

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Q: Assume that 20 parts are checked each hour and that X denotes

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Q: Suppose that a healthcare provider selects 20 patients randomly (without replacement

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Q: A utility company might offer electrical rates based on time-of

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Q: An article in Mathematical Biosciences [“Influence of Delayed Viral Production on

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Q: According to results from the analysis of chocolate bars in Chapter 3

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Q: Derive the formula for the mean and variance of an exponential random

Derive the formula for the mean and variance of an exponential random variable.

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Q: Suppose that x has a beta distribution with parameters α = 2

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Q: The length of stay at a hospital emergency department is the sum

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Suppose that the construction of a solar power station is initiated. The project’s completion time has not been set due to uncertainties in financial resources. The completion time for the first phase...

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Q: The length of stay at a specific emergency department in a hospital

The length of stay at a specific emergency department in a hospital in Phoenix, Arizona, had a mean of 4.6 hours. Assume that the length of stay is exponentially distributed. a. What is the standard d...

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Q: An article in the Journal of the National Cancer Institute [“Breast

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An article in Ad Hoc Networks [“Underwater Acoustic Sensor Networks: Target Size Detection and Performance Analysis” (2009, Vol. 7(4), pp. 803–808)] discussed an underwater acoustic sensor network to...

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Q: Suppose that X has an exponential distribution with mean equal to 10

Suppose that X has an exponential distribution with mean equal to 10. Determine the following: a. P(X > 10) b. P(X > 20) c. P(X < 30) d. Find the value of x such that P(X < x) = 0.95.

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Q: The total service time of a multistep manufacturing operation has a gamma

The total service time of a multistep manufacturing operation has a gamma distribution with mean 18 minutes and standard deviation 6. a. Determine the parameters λ and r of the distribution. b. Assume...

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Q: Suppose that X has an exponential distribution with a mean of 10

Suppose that X has an exponential distribution with a mean of 10. Determine the following: a. P(X < 5) b. P(X < 15 | X > 10) c. Compare the results in parts (a) and (b) and comment on the role of the...

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Q: Suppose that the log-ons to a computer network follow a

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Q: The life of automobile voltage regulators has an exponential distribution with a

The life of automobile voltage regulators has an exponential distribution with a mean life of 6 years. You purchase a 6-year-old automobile with a working voltage regulator and plan to own it for 6 ye...

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Q: The time between calls to a plumbing supply business is exponentially distributed

The time between calls to a plumbing supply business is exponentially distributed with a mean time between calls of 15 minutes. a. What is the probability that there are no calls within a 30-minute in...

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Q: The number of stork sightings on a route in South Carolina follows

The number of stork sightings on a route in South Carolina follows a Poisson process with a mean of 2.3 per year. a. What is the mean time between sightings? b. What is the probability that there are...

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Q: The time between arrivals of taxis at a busy intersection is exponentially

The time between arrivals of taxis at a busy intersection is exponentially distributed with a mean of 10 minutes. a. What is the probability that you wait longer than 1 hour for a taxi? b. Suppose tha...

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Q: The distance between major cracks in a highway follows an exponential distribution

The distance between major cracks in a highway follows an exponential distribution with a mean of 5 miles. a. What is the probability that there are no major cracks in a 10-mile stretch of the highway...

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Q: The probability density function of the length of a metal rod is

The probability density function of the length of a metal rod is f (x) = 2 for 2.3 < x < 2.8 meters. a. If the specifications for this process are from 2.25 to 2.75 meters, what proportion of rods fai...

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Q: Thewaiting time for service at a hospital emergency department (in hours

Thewaiting time for service at a hospital emergency department (in hours) follows a distribution with probability density function f (x) = 0.5 exp(−0.5x) for 0 < x.Determine the following: a. P(X < 0....

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Q: The conditional probability distribution of Y given X = x is fY

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Q: Given the probability density function f (x) = 0.

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Q: Consider the joint distribution in Exercise 5.1.1.

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A manufacturer of electroluminescent lamps knows that the amount of luminescent ink deposited on one of its products is normally distributed with a mean of 1.2 grams and a standard deviation of 0.03 g...

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An article in Health Economics [“Estimation of the TransitionMatrix of a Discrete-TimeMarkov Chain” (2002, Vol. 11, pp. 33–42)] considered the cha...

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Q: An article in Clinical Infectious Diseases [“Strengthening the Supply of Routinely

An article in Clinical Infectious Diseases [“Strengthening the Supply of Routinely Administered Vaccines in the United States: Problems and Proposed Solutions” (2006, Vol. 42(3), pp. S97–S103)] report...

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Q: The systolic and diastolic blood pressure values (mm Hg) are

The systolic and diastolic blood pressure values (mm Hg) are the pressures when the heart muscle contracts and relaxes (denoted as Y and X, respectively). Over a collection of individuals, the distrib...

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Q: For the Transaction Processing Performance Council’s benchmark in Exercise 5.1

For the Transaction Processing Performance Council’s benchmark in Exercise 5.1.6, let X, Y, and Z denote the average number of selects, updates, and inserts operations required for each type of transa...

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Q: Suppose that the random variables X, Y, and Z have

Suppose that the random variables X, Y, and Z have the following joint probability distribution. Determine the following: a. P(X = 2) b. P(X = 1, Y = 2) c. P(Z d. P(X = 1 or Z = 2) e. E(X) f. P(X =...

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Q: Suppose that the random variables X, Y, and Z have

Suppose that the random variables X, Y, and Z have the joint probability density function f (x, y, z) = 8xyz for 0 < x < 1, 0 < y < 1, and 0 < z < 1. Determine the following: a. P(X < 0.5) b. P(X < 0...

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Q: Calls to a telephone system follow a Poisson process with a mean

Calls to a telephone system follow a Poisson process with a mean of five calls per minute. a. What is the name applied to the distribution and parameter values of the time until the 10th call? b. What...

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Q: Suppose that the random variables X, Y, and Z have

Suppose that the random variables X, Y, and Z have the joint probability density function fXYZ(x, y, z) = c over the cylinder x2 + y2 < 4 and 0 < z < 4. Determine the constant c so that fXYZ(x, y, z)...

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Q: Determine the mean and variance of the random variable in Exercise 4

Determine the mean and variance of the random variable in Exercise 4.1.10.

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Q: Suppose that the probability density function of the length of computer cables

Suppose that the probability density function of the length of computer cables is f (x) = 0.1 from 1200 to 1210 millimeters. a. Determine the mean and standard deviation of the cable length. b. If the...

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Q: The thickness of a conductive coating in micrometers has a density function

The thickness of a conductive coating in micrometers has a density function of 600x−2 for 100 μm < x < 120 μm. a. Determine the mean and variance of the coating thickness. b. If the coating costs $0.5...

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Q: Suppose that f (x) = 1.5x2 for −

Suppose that f (x) = 1.5x2 for −1 < x < 1. Determine the mean and variance of X.

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Q: Suppose that f (x) = 0.125x for 0

Suppose that f (x) = 0.125x for 0 < x < 4. Determine the mean and variance of X.

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Q: Determine the mean and variance of the random variable in Exercise 4

Determine the mean and variance of the random variable in Exercise 4.1.1.

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Q: Determine the mean and variance of the random variable in Exercise 4

Determine the mean and variance of the random variable in Exercise 4.1.8.

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Q: Suppose that X has a lognormal distribution with parameters θ = 5

Suppose that X has a lognormal distribution with parameters θ = 5 and ω2 = 9. Determine the following: a. P(X < 13,300) b. Value for x such that P(X ≤ x) = 0.95 c. Mean and variance of X

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Q: Suppose that X has a lognormal distribution with parameters θ = 2

Suppose that X has a lognormal distribution with parameters θ = 2 and ω2 = 4. Determine the following in parts (a) and (b): a. P(X < 500) b. Conditional probability that X < 1500 given that X > 1000 c...

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Q: Rawmaterials are studied for contamination. Suppose that the number of particles

Rawmaterials are studied for contamination. Suppose that the number of particles of contamination per pound of material is a Poisson random variable with a mean of 0.01 particle per pound. a. What is...

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Q: The length of time (in seconds) that a user views

The length of time (in seconds) that a user views a page on a Web site before moving to another page is a lognormal random variable with parameters θ = 0.5 and ω2 = 1. a. What is the probability that...

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Q: Suppose that X has a lognormal distribution and that the mean and

Suppose that X has a lognormal distribution and that the mean and variance of X are 100 and 85,000, respectively. Determine the parameters θ and ω2 of the lognormal distribution. [Hint: Define u = exp...

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Q: The lifetime of a semiconductor laser has a lognormal distribution, and

The lifetime of a semiconductor laser has a lognormal distribution, and it is known that the mean and standard deviation of lifetime are 10,000 and 20,000, respectively. a. Calculate the parameters of...

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Q: An article in Health and Population: Perspectives and Issues (2000

An article in Health and Population: Perspectives and Issues (2000, Vol. 23, pp. 28–36) used the lognormal distribution to model blood pressure in humans. The mean systolic blood pressure (SBP) in mal...

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Q: Suppose that the length of stay (in hours) at a

Suppose that the length of stay (in hours) at a hospital emergency department is modeled with a lognormal random variable X with θ = 1.5 and ω = 0.4. Determine the following in parts (a) and (b): a. M...

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Q: An article in Journal of Hydrology [“Use of a Lognormal Distribution

An article in Journal of Hydrology [“Use of a Lognormal Distribution Model for Estimating Soil Water Retention Curves from Particle-Size Distribution Data” (2006, Vol. 323(1), pp. 325–334)] considered...

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Q: An article in AppliedMathematics and Computation [“Confidence Intervals for Steady State

An article in AppliedMathematics and Computation [“Confidence Intervals for Steady State Availability of a System with Exponential Operating Time and Lognormal Repair Time” (2003, Vol. 137(2), pp. 499...

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Q: An article in Chemosphere [“Statistical Evaluations Reflecting the Skewness in the

An article in Chemosphere [“Statistical Evaluations Reflecting the Skewness in the Distribution of TCDD Levels in Human Adipose Tissue” (1987, Vol. 16(8), pp. 2135–2140)] concluded that the levels of...

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Q: Determine the value of c that makes the function f (x

Determine the value of c that makes the function f (x, y) = c(x + y) a joint probability density function over the range 0 < x < 3 and x < y < x + 2. Determine the following: a. P(X < 1, Y < 2) b. P(...

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Q: Consider the joint distribution in Exercise 5.1.10.

Consider the joint distribution in Exercise 5.1.10. Determine the following: a. fY | 2(y) b. E(Y | X = 2) c. V(Y | X = 2) d. Are X and Y independent?

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Q: The time between arrivals of customers at an automatic teller machine is

The time between arrivals of customers at an automatic teller machine is an exponential random variable with a mean of 5 minutes. a. What is the probability that more than three customers arrive in 10...

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Q: Determine the cumulative distribution function for the random variable in Exercise 4

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Q: Determine the cumulative distribution function for the random variable in Exercise 4

Determine the cumulative distribution function for the random variable in Exercise 4.1.9. Use the cumulative distribution function to determine the probability that the waiting time is less than 1 hou...

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Q: Determine the cumulative distribution function for the random variable in Exercise 4

Determine the cumulative distribution function for the random variable in Exercise 4.1.8. Use the cumulative distribution function to determine the probability that 400 < X < 500.

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Q: Suppose that the cumulative distribution function of the random variable X is

Suppose that the cumulative distribution function of the random variable X is Determine the following: a. P(X b. P(X > 1.5) c. P(X d. P(X > 6)

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Q: Determine the cumulative distribution function for the distribution in Exercise 4.

Determine the cumulative distribution function for the distribution in Exercise 4.1.1.

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Q: Determine the cumulative distribution function for the distribution in Exercise 4.

Determine the cumulative distribution function for the distribution in Exercise 4.1.3.

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Q: Determine the covariance and correlation for the following joint probability distribution:

Determine the covariance and correlation for the following joint probability distribution:

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Q: Determine the value for c and the covariance and correlation for the

Determine the value for c and the covariance and correlation for the joint probability mass function fXY (x, y) = c(x + y) for x = 1, 2, 3 and y = 1, 2, 3.

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Q: Patients are given a drug treatment and then evaluated. Symptoms either

Patients are given a drug treatment and then evaluated. Symptoms either improve, degrade, or remain the same with probabilities 0.4, 0.1, 0.5, respectively. Assume that four independent patients are t...

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Q: For the Transaction Processing Performance Council’s benchmark in Exercise 5.1

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Q: In a data communication system, several messages that arrive at a

In a data communication system, several messages that arrive at a node are bundled into a packet before they are transmitted over the network. Assume that the messages arrive at the node according to...

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Q: X and Y are independent, normal random variables with E(

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Q: Suppose that the random variable X represents the length of a punched

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In the manufacture of electroluminescent lamps, several different layers of ink are deposited onto a plastic substrate. The thickness of these layers is critical if specifications regarding the final...

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Q: Making handcrafted pottery generally takes two major steps: wheel throwing and

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Q: Assume that the weights of individuals are independent and normally distributed with

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Q: The rate of return of an asset is the change in price

The rate of return of an asset is the change in price divided by the initial price (denoted as r). Suppose that $10,000 is used to purchase shares in three stocks with rates of returns X1, X2, X3. Ini...

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Q: Patients arrive at a hospital emergency department according to a Poisson process

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Q: In Exercise 5.2.7, the monthly demand for

In Exercise 5.2.7, the monthly demand for MMR vaccine was assumed to be approximately normally distributed with a mean and standard deviation of 1.1 and 0.3 million doses, respectively. Suppose that t...

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Q: Suppose that X is a binomial random variable with n = 200

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Q: Cabs pass your workplace according to a Poisson process with a mean

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Q: The number of (large) inclusions in cast iron follows a

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Q: Suppose that X is a Poisson random variable with λ = 6

Suppose that X is a Poisson random variable with λ = 6. a. Compute the exact probability that X is less than four. b. Approximate the probability that X is less than four and compare to the result in...

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Q: There were 49.7 million people with some type of long

There were 49.7 million people with some type of long-lasting condition or disability living in the United States in 2000. This represented 19.3 percent of the majority of civilians aged five and over...

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Q: The manufacturing of semiconductor chips produces 2% defective chips. Assume

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Q: Hits to a high-volumeWeb site are assumed to follow a

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Q: Phoenix water is provided to approximately 1.4 million people who

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Q: An article in Atmospheric Chemistry and Physics [“Relationship Between Particulate Matter

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Q: Use integration by parts to show that Γ(r) =

Use integration by parts to show that Γ(r) = (r −1) Γ(r − 1).

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Q: An acticle in Biometrics [“Integrative Analysis of Transcriptomic and Proteomic Data

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Q: If X is a Weibull random variable with β = 1 and

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Q: Suppose that X has a Weibull distribution with β = 0.

Suppose that X has a Weibull distribution with β = 0.2 and δ = 100 hours. Determine the following: a. P(X < 10,000) b. P(X > 5000) c. E(X) and V(X)

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Q: The life (in hours) of a magnetic resonance imaging machine

The life (in hours) of a magnetic resonance imaging machine (MRI) is modeled by a Weibull distribution with parameters β = 2 and δ = 500 hours. Determine the following: a. Mean life of the MRI b. Vari...

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Q: Assume that the life of a roller bearing follows a Weibull distribution

Assume that the life of a roller bearing follows a Weibull distribution with parameters β = 2 and δ = 10,000 hours. a. Determine the probability that a bearing lasts at least 8000 hours. b. Determine...

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Q: An article in the Journal of Geophysical Research [“Spatial and Temporal

An article in the Journal of Geophysical Research [“Spatial and Temporal Distributions of U.S. Winds and Wind Power at 80 m Derived from Measurements” (2003, Vol. 108)] considered wind speed at statio...

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Q: An article in the Journal of the Indian Geophysical Union titled “

An article in the Journal of the Indian Geophysical Union titled “Weibull and Gamma Distributions for Wave Parameter Predictions” (2005, Vol. 9, pp. 55–64) described the use of the Weibull distributio...

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Q: Suppose that the lifetime of a component (in hours) is

Suppose that the lifetime of a component (in hours) is modeled with a Weibull distribution with β = 2 and δ = 4000. Determine the following in parts (a) and (b): a. P(X > 5000) b. P(X > 8000 | X > 300...

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Q: Suppose that X has a Weibull distribution with β = 2 and

Suppose that X has a Weibull distribution with β = 2 and δ = 8.6. Determine the following: a. P(X < 10) b. P(X > 9) c. P(8 < X < 11) d. Value for x such that P(X > x) = 0.9

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Q: An article in Proceedings of the 33rd International ACM SIGIR Conference on

An article in Proceedings of the 33rd International ACM SIGIR Conference on Research and Development in Information Retrieval [“Understanding Web Browsing Behaviors Through Weibull Analysis of Dwell T...

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Q: The geometric random variable X has probability distribution f (x)

The geometric random variable X has probability distribution f (x) = (1 − p)x−1p, x = 1, 2,… a. Show that the moment-generating function is b. U...

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Q: An article in Sensors and Actuators A: Physical [“Characterization and

An article in Sensors and Actuators A: Physical [“Characterization and Simulation of Avalanche PhotoDiodes for Next-Generation Colliders” (2011, Vol. 172(1), pp. 181–188)] considered an avalanche phot...

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Q: An article in Electronic Journal of Applied Statistical Analysis [“Survival Analysis

An article in Electronic Journal of Applied Statistical Analysis [“Survival Analysis of Dialysis Patients Under Parametric and Non-Parametric Approaches” (2012, Vol. 5(2), pp. 271–288)] modeled the su...

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Q: An article in IEEE Transactions on Dielectrics and Electrical Insulation [“Statistical

An article in IEEE Transactions on Dielectrics and Electrical Insulation [“Statistical Analysis of the AC Breakdown Voltages of Ester Based Transformer Oils” (2008, Vol. 15(4), pp. 1044–1050)] used We...

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Q: An article in Financial Markets Institutions and Instruments [“Pricing Reinsurance Contracts

An article in Financial Markets Institutions and Instruments [“Pricing Reinsurance Contracts on FDIC Losses” (2008, Vol. 17(3), pp. 225–247)] modeled average annual losses (in billions of dollars) of...

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Q: A set of 200 independent patients take antiacid medication at the start

A set of 200 independent patients take antiacid medication at the start of symptoms, and 80 experience moderate to substantial relief within 90 minutes. Historically, 30% of patients experience relief...

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Q: Assume that X is normally distributed with a mean of 10 and

Assume that X is normally distributed with a mean of 10 and a standard deviation of 2. Determine the following: a. P(Z < 13) b. P(Z > 9) c. P(6 < X < 14) d. P(2 < X < 4) e. P(−2 < X < 8)

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Q: Assume that X is normally distributed with a mean of 10 and

Assume that X is normally distributed with a mean of 10 and a standard deviation of 2. Determine the value for x that solves each of the following: a. P(X > x) = 0.5 b. P(X > x) = 0.95 c. P(x < X < 1...

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Q: An article in Knee Surgery Sports Traumatology Arthroscopy [“Effect of Provider

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Q: The time until recharge for a battery in a laptop computer under

The time until recharge for a battery in a laptop computer under common conditions is normally distributed with a mean of 260 minutes and a standard deviation of 50 minutes. a. What is the probability...

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Q: A driver’s reaction time to visual stimulus is normally distributed with a

A driver’s reaction time to visual stimulus is normally distributed with a mean of 0.4 seconds and a standard deviation of 0.05 seconds. a. What is the probability that a reaction requires more than 0...

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Q: Cholesterol is a fatty substance that is an important part of the

Cholesterol is a fatty substance that is an important part of the outer lining (membrane) of cells in the body of animals. Its normal range for an adult is 120–240 mg/dl. The Food and Nutrition Instit...

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Q: Determine the covariance and correlation for the lengths of the minor and

Determine the covariance and correlation for the lengths of the minor and major axes in Exercise 5.2.5.

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Q: Based on the number of voids, a ferrite slab is classified

Based on the number of voids, a ferrite slab is classified as either high, medium, or low. Historically, 5% of the slabs are classified as high, 85% as medium, and 10% as low. Agroup of 20 slabs that...

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Q: A Web site uses ads to route visitors to one of four

A Web site uses ads to route visitors to one of four landing pages. The probabilities for each landing page are equal. Consider 20 independent visitors and let the random variablesW, X, Y, and Z denot...

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Q: Suppose that X and Y have a bivariate normal distribution with σX

Suppose that X and Y have a bivariate normal distribution with σX = 0.04, σY = 0.08, μX = 3.00, μY = 7.70, and ρ = 0. Determine the following: a. P(2.95 < X < 3.05) b. P(7.60 < Y < 7.80) c. P(2.95 <...

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Q: Let X and Y represent the concentration and viscosity of a chemical

Let X and Y represent the concentration and viscosity of a chemical product. Suppose that X and Y have a bivariate normal distribution with σX = 4, σY = 1, μX = 2, and μY = 1. Draw a rough contour plo...

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Q: In the manufacture of electroluminescent lamps, several different layers of ink

In the manufacture of electroluminescent lamps, several different layers of ink are deposited onto a plastic substrate. The thickness of these layers is critical if specifications regarding the final...

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Q: In an acid-base titration, a base or acid is

In an acid-base titration, a base or acid is gradually added to the other until they have completely neutralized each other. Let X and Y denote the milliliters of acid and base needed for equivalence,...

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Q: If X and Y have a bivariate normal distribution with ρ =

If X and Y have a bivariate normal distribution with ρ = 0, show that X and Y are independent.

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Q: Patients given drug therapy either improve, remain the same, or

Patients given drug therapy either improve, remain the same, or degrade with probabilities 0.5, 0.4, and 0.1, respectively. Suppose that 20 patients (assumed to be independent) are given the therapy....

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Q: In an accelerator center, an experiment needs a 1.41

In an accelerator center, an experiment needs a 1.41-cmthick aluminum cylinder (http://puhep1.princeton.edu/mumu/ target/Solenoid_Coil.pdf ). Suppose that the thickness of a cylinder has a normal dist...

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Q: In 2002, the average height of a woman aged 20–

In 2002, the average height of a woman aged 20–74 years was 64 inches, with an increase of approximately 1 inch from 1960 (http://usgovinfo.about.com/od/healthcare). Suppose the height of a woman is n...

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Q: Suppose that the correlation between X and Y is ρ. For

Suppose that the correlation between X and Y is ρ. For constants a, b, c, and d, what is the correlation between the random variables U = aX + b and V = cY + d?

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Q: The life of a semiconductor laser at a constant power is normally

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Q: The demand for water use in Phoenix in 2003 hit a high

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Q: The weight of a running shoe is normally distributed with a mean

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Q: The diameter of the dot produced by a printer is normally distributed

The diameter of the dot produced by a printer is normally distributed with a mean diameter of 0.002 inch and a standard deviation of 0.0004 inch. a. What is the probability that the diameter of a dot...

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Q: Assume that a random variable is normally distributed with a mean of

Assume that a random variable is normally distributed with a mean of 24 and a standard deviation of 2. Consider an interval of length one unit that starts at the value a so that the interval is [a, a...

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Q: The length of stay at a specific emergency department in Phoenix,

The length of stay at a specific emergency department in Phoenix, Arizona, in 2009 had a mean of 4.6 hours with a standard deviation of 2.9. Assume that the length of stay is normally distributed. a....

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Q: A signal in a communication channel is detected when the voltage is

A signal in a communication channel is detected when the voltage is higher than 1.5 volts in absolute value. Assume that the voltage is normally distributed with a mean of 0. What is the standard devi...

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Q: An article in the Journal of Cardiovascular Magnetic Resonance [“Right Ventricular

An article in the Journal of Cardiovascular Magnetic Resonance [“Right Ventricular Ejection Fraction Is Better Reflected by Transverse Rather Than Longitudinal Wall Motion in Pulmonary Hypertension” (...

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Q: Suppose X has a continuous uniformdistribution over the interval [−1,

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Q: Use Appendix Table III to determine the following probabilities for the standard

Use Appendix Table III to determine the following probabilities for the standard normal random variable Z: a. P(Z < 1.32) b. P(Z < 3.0) c. P(Z > 1.45) d. P(Z > −2.15) e. P(−2.34 < Z < 1.76)

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Q: Assume that Z has a standard normal distribution. Use Appendix Table

Assume that Z has a standard normal distribution. Use Appendix Table III to determine the value for z that solves each of the following: a. P(−z < Z < z) = 0.95 b. P(−z < Z < z) = 0.99 c. P(−z < Z <...

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Q: Determine the value for c and the covariance and correlation for the

Determine the value for c and the covariance and correlation for the joint probability density function fXY (x, y) = cxy over the range 0 < x < 3 and 0 < y < x.

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Q: Determine the covariance and correlation for the joint probability density function fXY

Determine the covariance and correlation for the joint probability density function fXY (x, y) = e−x−y over the range 0 < x and 0 < y.

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Q: The joint probability distribution is / Show that the correlation

The joint probability distribution is Show that the correlation between X and Y is zero but X and Y are not independent.

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Q: Determine the covariance and correlation for the CD4 counts in a month

Determine the covariance and correlation for the CD4 counts in a month and the following month in Exercise 5.2.6.

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Q: A random variable X has the discrete uniform distribution /

A random variable X has the discrete uniform distribution a. Show that the moment-generating function is b. Use MX(t) to find the mean and variance of X.

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Q: The thickness of a flange on an aircraft component is uniformly distributed

The thickness of a flange on an aircraft component is uniformly distributed between 0.95 and 1.05 millimeters. Determine the following: a. Cumulative distribution function of flange thickness b. Propo...

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Q: The thickness of photoresist applied towafers in semiconductor manufacturing at a particular

The thickness of photoresist applied towafers in semiconductor manufacturing at a particular location on the wafer is uniformly distributed between 0.2050 and 0.2150 micrometers. Determine the followi...

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Q: An adult can lose or gain two pounds of water in the

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Q: A show is scheduled to start at 9:00 A.

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Q: The volume of a shampoo filled into a container is uniformly distributed

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Q: An e-mail message will arrive at a time uniformly distributed

An e-mail message will arrive at a time uniformly distributed between 9:00 A.M. and 11:00 A.M. You check e-mail at 9:15 A.M. and every 30 minutes afterward. a. What is the standard deviation of arriva...

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Q: The chi-squared random variable with k degrees of freedom has

The chi-squared random variable with k degrees of freedom has moment-generating function MX(t) = (1 − 2t)−k∕2. Suppose that X1 and X2 are independent chi-squared random variableswith k1 and k2 degrees...

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Q: An electron emitter produces electron beams with changing kinetic energy that is

An electron emitter produces electron beams with changing kinetic energy that is uniformly distributed between 3 and 7 joules. Suppose that it is possible to adjust the upper limit of the kinetic ener...

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Q: Determine the cumulative distribution function for the distribution in Exercise 4.

Determine the cumulative distribution function for the distribution in Exercise 4.1.2.

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Q: Determine the cumulative distribution function for the distribution in Exercise 4.

Determine the cumulative distribution function for the distribution in Exercise 4.1.4.

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Q: The probability density function of the time you arrive at a terminal

The probability density function of the time you arrive at a terminal (in minutes after 8:00 A.M.) is f (x) = 0.1 exp(−0.1x) for 0 < x. Determine the probability that a. You arrive by 9:00 A.M. b. You...

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Q: The probability density function of the time it takes a hematology cell

The probability density function of the time it takes a hematology cell counter to complete a test on a blood sample is f (x) = 0.04 for 50 < x < 75 seconds. a. What percentage of tests requires more...

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Q: The time it takes a cell to divide (called mitosis)

The time it takes a cell to divide (called mitosis) is normally distributed with an average time of 1 hour and a standard deviation of 5 minutes. a. What is the probability that a cell divides in less...

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Q: The sick-leave time of employees in a firmin a month

The sick-leave time of employees in a firmin a month is normally distributed with a mean of 100 hours and a standard deviation of 20 hours. a. What is the probability that the sick-leave time for next...

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Q: Show that the following function satisfies the properties of a joint probability

Show that the following function satisfies the properties of a joint probability mass function: Determine the following: a. P(X c. P(X 0.5, Y e. E(X), E(Y), V(X), V(Y) f. Marginal probability distrib...

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Q: The percentage of people given an antirheumatoid medication who suffer severe,

The percentage of people given an antirheumatoid medication who suffer severe, moderate, or minor side effects are 10, 20, and 70%, respectively. Assume that people react independently and that 20 peo...

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Q: Determine the value of c such that the function f (x

Determine the value of c such that the function f (x, y) = cx2y for 0 < x < 3 and 0 < y < 2 satisfies the properties of a joint probability density function. Determine the following: a. P(X < 1, Y < 1...

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Q: A continuous random variable X has the following probability distribution:

A continuous random variable X has the following probability distribution: f (x) = 4xe−2x , x > 0 a. Find the moment-generating function for X. b. Find the mean and variance of X.

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Q: The joint distribution of the continuous random variables X, Y,

The joint distribution of the continuous random variables X, Y, and Z is constant over the region x2 + y2 ≤ 1, 0 < z < 4. Determine the following: a. P(X2 + Y2 ≤ 0.5) b. P(X2 + Y2 ≤ 0.5, Z < 2) c. Jo...

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Q: Contamination problems in semiconductormanufacturing can result in a functional defect, a

Contamination problems in semiconductormanufacturing can result in a functional defect, a minor defect, or no defect in the final product. Suppose that 20%, 50%, and 30% of the contamination problems...

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Q: The time for an automated system in a warehouse to locate a

The time for an automated system in a warehouse to locate a part is normally distributed with a mean of 45 seconds and a standard deviation of 30 seconds. Suppose that independent requests are made fo...

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Q: The weight of a small candy is normally distributed with a mean

The weight of a small candy is normally distributed with a mean of 0.1 ounce and a standard deviation of 0.01 ounce. Suppose that 16 candies are placed in a package and that the weights are independen...

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Q: Suppose that X and Y have a bivariate normal distribution with σX

Suppose that X and Y have a bivariate normal distribution with σX = 4, σY = 1, μX = 2, μY = 4, and ρ = −0.2. Draw a rough contour plot of the joint probability density function.

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Q: A mechanical assembly used in an automobile engine contains four major components

A mechanical assembly used in an automobile engine contains four major components. The weights of the components are independent and normally distributed with the following means and standard deviatio...

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Q: The permeability of a membrane used as a moisture barrier in a

The permeability of a membrane used as a moisture barrier in a biological application depends on the thickness of two integrated layers. The layers are normally distributed with means of 0.5 and 1 mil...

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Q: Amarketing company performed a risk analysis for a manufacturer of synthetic fibers

Amarketing company performed a risk analysis for a manufacturer of synthetic fibers and concluded that new competitors present no risk 13% of the time (due mostly to the diversity of fibers manufactur...

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Q: The continuous uniform random variable X has density function /

The continuous uniform random variable X has density function a. Show that the moment-generating function is b. Use MX(t) to find the mean and variance of X.

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Q: Suppose X has a lognormal distribution with parameters θ and ω.

Suppose X has a lognormal distribution with parameters θ and ω. Determine the probability density function and the parameters values for Y = Xγ for a constant γ > 0. What is the name of this distribut...

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Q: The power in a DC circuit is P = I2/R

The power in a DC circuit is P = I2/R where I and R denote the current and resistance, respectively. Suppose that I is approximately normally distributed with mean of 200 mA and standard deviation 0.2...

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Q: The intensity (mW/mm2) of a laser beam on

The intensity (mW/mm2) of a laser beam on a surface theoretically follows a bivariate normal distribution with maximum intensity at the center, equal variance σ in the x and y directions, and zero cov...

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Q: Consider the regional right ventricle transverse wall motion in patients with pulmonary

Consider the regional right ventricle transverse wall motion in patients with pulmonary hypertension (PH). The right-ventricle ejection fraction (EF) is approximately normally distributed with a stand...

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Q: Provide approximate sketches for beta probability density functions with the following parameters

Provide approximate sketches for beta probability density functions with the following parameters. Comment on any symmetries and show any peaks in the probability density functions in the sketches. a....

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Q: Among homeowners in a metropolitan area, 25% recycle paper each

Among homeowners in a metropolitan area, 25% recycle paper each week. A waste management company services 10,000 homeowners (assumed independent). Approximate the following probabilities: a. More than...

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Q: An article in Journal of Theoretical Biology [“Computer Model of Growth

An article in Journal of Theoretical Biology [“Computer Model of Growth Cone Behavior and Neuronal Morphogenesis” (1995, Vol. 174(4), pp. 381–389)] developed a model for neuronal morphogenesis in whic...

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Q: An article in Electric Power Systems Research [“On the Self-

An article in Electric Power Systems Research [“On the Self-Scheduling of a Power Producer in Uncertain Trading Environments” (2008, Vol. 78(3), pp. 311–317)] considered a self-scheduling approach for...

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Q: An article in Electronic Journal of Applied Statistical Analysis [“Survival Analysis

An article in Electronic Journal of Applied Statistical Analysis [“Survival Analysis of Acute Myocardial Infarction Patients Using Non-Parametric and Parametric Approaches” (2009, Vol. 2(1), pp. 22–36...

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Q: The percentage of people exposed to a bacteria who become ill is

The percentage of people exposed to a bacteria who become ill is 20%. Assume that people are independent. Assume that 1000 people are exposed to the bacteria. Approximate each of the following: a. Pro...

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Q: The time to failure (in hours) for a laser in

The time to failure (in hours) for a laser in a cytometry machine is modeled by an exponential distribution with λ = 0.00004. What is the probability that the time until failure is a. At least 20,000...

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Q: When a bus service reduces fares, a particular trip from New

When a bus service reduces fares, a particular trip from New York City to Albany, New York, is very popular. A small bus can carry four passengers. The time between calls for tickets is exponentially...

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Q: The size of silver particles in a photographic emulsion is known to

The size of silver particles in a photographic emulsion is known to have a log normal distribution with a mean of 0.001mm and a standard deviation of 0.002 mm. a. Determine the parameter values for th...

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Q: The life of a recirculating pump follows a Weibull distribution with parameters

The life of a recirculating pump follows a Weibull distribution with parameters β = 2 and δ = 700 hours. Determine for parts (a) and (b): a. Mean life of a pump b. Variance of the life of a pump c. Wh...

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Q: The time between calls is exponentially distributed with a mean time between

The time between calls is exponentially distributed with a mean time between calls of 10 minutes. a. What is the probability that the time until the first call is less than five minutes? b. What is th...

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Q: Suppose that f (x) = 0.5x − 1

Suppose that f (x) = 0.5x − 1 for 2 < x < 4. Determine the following: a. P(X < 2.5) b. P(X > 3) c. P(2.5 < X < 3.5) d. Determine the cumulative distribution function of therandom variable. e. Determ...

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Q: Suppose that X has a lognormal distribution with parameters θ = 0

Suppose that X has a lognormal distribution with parameters θ = 0 and ω2 = 4. Determine the following: a. P(10 < X < 50) b. Value for x such that P(X < x) = 0.05 c. Mean and variance of X

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Q: Suppose that X has a lognormal distribution and that the mean and

Suppose that X has a lognormal distribution and that the mean and variance of X are 50 and 4000, respectively. Determine the following: a. Parameters θ and ω2 of the lognormal distribution b. Probabil...

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Q: Asbestos fibers in a dust sample are identified by an electron microscope

Asbestos fibers in a dust sample are identified by an electron microscope after sample preparation. Suppose that the number of fibers is a Poisson random variable and the mean number of fibers per squ...

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Q: The waiting time for service at a hospital emergency department follows an

The waiting time for service at a hospital emergency department follows an exponential distribution with a mean of three hours. Determine the following: a. Waiting time is greater than four hours b. W...

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Q: A random variable X has the gamma distribution / a

A random variable X has the gamma distribution a. Show that the moment-generating function for t b. Find the mean and variance of X.

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Q: The diameter of the dot produced by a printer is normally distributed

The diameter of the dot produced by a printer is normally distributed with a mean diameter of 0.002 inch. a. Suppose that the specifications require the dot diameter to be between 0.0014 and 0.0026 in...

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Q: A square inch of carpeting contains 50 carpet fibers. The probability

A square inch of carpeting contains 50 carpet fibers. The probability of a damaged fiber is 0.0001. Assume that the damaged fibers occur independently. a. Approximate the probability of one or more da...

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Q: An airline makes 200 reservations for a flight that holds 185 passengers

An airline makes 200 reservations for a flight that holds 185 passengers. The probability that a passenger arrives for the flight is 0.9, and the passengers are assumed to be independent. a. Approxima...

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Q: Suppose that the construction of a solar power station is initiated.

Suppose that the construction of a solar power station is initiated. The project’s completion time has not been set due to uncertainties in financial resources. The proportion of completion within one...

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Q: An article in IEEE Journal on Selected Areas in Communications [“Impulse

An article in IEEE Journal on Selected Areas in Communications [“Impulse Response Modeling of Indoor Radio Propagation Channels” (1993, Vol. 11(7), pp. 967–978)] indicated that the successful design o...

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Q: Determine the cumulative distribution function for the distribution in Exercise 4.

Determine the cumulative distribution function for the distribution in Exercise 4.1.7. Use the cumulative distribution function to determine the probability that a length exceeds 2.7 meters.

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Q: F(x) = 1 − e−2x x >

F(x) = 1 − e−2x x > 0

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Q: Solve the following /

Solve the following

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Q: Show that the following function satisfies the properties of a joint probability

Show that the following function satisfies the properties of a joint probability mass function. Determine the following: a. P(X b. P(X c. P(Y d. P(X > 1.8, Y > 4.7) e. E(X), E(Y), V(X), V(Y) f....

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Q: Show that the following function satisfies the properties of a joint probability

Show that the following function satisfies the properties of a joint probability mass function. Determine the following: a. P(X b. P(X c. P(Y d. P(X > 0.25, Y e. E(X), E(Y), V(X), V(Y) f. Marginal...

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Q: Let X1, X2,…, Xr be independent exponential random variables with

Let X1, X2,…, Xr be independent exponential random variables with parameter λ. a. Find the moment-generating function of Y = X1 + X2 + …+Xr. b. What is the distribution of the random variable Y?

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Q: In the transmission of digital information, the probability that a bit

In the transmission of digital information, the probability that a bit has high, moderate, and low distortion is 0.01, 0.04, and 0.95, respectively. Suppose that three bits are transmitted and that th...

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Q: A small-business Web site contains 100 pages and 60%,

A small-business Web site contains 100 pages and 60%, 30%, and 10% of the pages contain low, moderate, and high graphic content, respectively. A sample of four pages is selected randomly without repla...

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Q: A manufacturing company employs two devices to inspect output for quality control

A manufacturing company employs two devices to inspect output for quality control purposes. The first device is able to accurately detect 99.3% of the defective items it receives, whereas the second i...

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Q: An article in the Journal of Database Management [“Experimental Study of

An article in the Journal of Database Management [“Experimental Study of a Self-Tuning Algorithm for DBMS Buffer Pools” (2005, Vol. 16, pp. 1–20)] provided the workload used in the TPC-C OLTP (Transac...

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Q: An engineering statistics class has 40 students; 60% are electrical

An engineering statistics class has 40 students; 60% are electrical engineering majors, 10% are industrial engineering majors, and 30% are mechanical engineering majors. A sample of four students is s...

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Q: An article in Electric Power Systems Research [“Modeling Real-Time

An article in Electric Power Systems Research [“Modeling Real-Time Balancing Power Demands in Wind Power Systems Using Stochastic Differential Equations” (2010, Vol...

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Q: Determine the value of c such that the function f (x

Determine the value of c such that the function f (x, y) = cxy for 0 < x < 3 and 0 < y < 3 satisfies the properties of a joint probability density function. Determine the following: a. P(X < 2, Y < 3)...

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Q: Determine the value of c that makes the function f (x

Determine the value of c that makes the function f (x, y) = ce−2x−3y a joint probability density function over the range 0 < x and x < y. Determine the following: a. P(X < 1, Y < 2) b. P(1 < X < 2) c...

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Q: Suppose that f (x) = e−x for 0

Suppose that f (x) = e−x for 0 < x. Determine the following: a. P(1 < X) b. P(1 < X < 2.5) c. P(X = 3) d. P(X < 4) e. P(3 ≤ X) f. x such that P(x < X) = 0.10 g. x such that P(X ≤ x) = 0.10

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Q: The distribution of X is approximated with a triangular probability density function

The distribution of X is approximated with a triangular probability density function f (x) = 0.0025x − 0.075 for 30 < x < 50 and f (x) = −0.0025x + 0.175 for 50 < x < 70. Determine the following: a. P...

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Q: Suppose that Xi has a normal distribution with mean μi and variance

Suppose that Xi has a normal distribution with mean μi and variance σ2i , i = 1, 2. Let X1 and X2 be independent. a. Find the moment-generating function of Y = X1 + X2. b. What is the distribution of...

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Q: The diameter of a particle of contamination (in micrometers) is

The diameter of a particle of contamination (in micrometers) is modeled with the probability density function f (x) = 2∕x3 for x > 1. Determine the following: a. P(X < 2) b. P(X > 5) c. P(4 < X < 8)...

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Q: Suppose that f (x) = 0.5 cos x

Suppose that f (x) = 0.5 cos x for −π∕2 < x < π∕2. Determine the following: a. P(X < 0) b. P(X < −π∕4) c. P(−π∕4 < X < π∕4) d. P(X > −π∕4) e. x such that P(X < x) = 0.95

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Q: Suppose that f (x) = x∕8 for 3

Suppose that f (x) = x∕8 for 3 < x < 5. Determine the following probabilities: a. P(X < 4) b. P(X > 3.5) c. P(4 < X < 5) d. P(X < 4.5) e. P(X < 3.5 or X > 4.5)

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Q: Suppose that f (x) = 1.5x2 for −

Suppose that f (x) = 1.5x2 for −1 < x < 1. Determine the following: a. P(0 < X) b. P(0.5 < X) c. P(−0.5 ≤ X ≤ 0.5) d. P(X < −2) e. P(X < 0 or X > −0.5) f. x such that P(x < X) = 0.05.

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Q: The probability density function of the net weight in pounds of a

The probability density function of the net weight in pounds of a packaged chemical herbicide is f (x) = 2.0 for 49.75 < x < 50.25 pounds. a. Determine the probability that a package weighs more than...

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Q: Suppose that X is a random variable with probability distribution fX

Suppose that X is a random variable with probability distribution fX(x) = 1∕4, x = 1, 2, 3, 4 Determine the probability distribution of Y = 2X + 1.

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Q: Suppose that X is a continuous random variable with probability distribution

Suppose that X is a continuous random variable with probability distribution fX(x) = x /18 , 0 ≤ x ≤ 6 a. Determine the probability distribution of the random variable Y = 2X + 10. b. Determine the ex...

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Q: A random variable X has the probability distribution fX(x

A random variable X has the probability distribution fX(x) = e−x , x ≥ 0 Determine the probability distribution for the following: a. Y = X2 b. Y = X1/2 c. Y = ln X

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Q: The velocity of a particle in a gas is a random variable

The velocity of a particle in a gas is a random variable V with probability distribution fV (v) = av2e−bv , v > 0 where b is a constant that depends on the temperature of the gas and the mass of the p...

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Q: Suppose that X has the probability distribution fX(x)

Suppose that X has the probability distribution fX(x) = 1, 1 ≤ x ≤ 2 Determine the probability distribution of the random variable Y = eX.

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