Question: A school board at a local community

> The trade volume of a stock is the number of shares traded on a given day. The following data, in millions (so that 6.16 represents 6,160,000 shares traded), represent the volume of PepsiCo stock traded for a random sample of 40 trading days in 2018. (a)

> The following data represent the wait time (in minutes) for a random sample of 40 visitors to Disney’s Dinosaur Ride in Animal Kingdom. (a) Draw a relative frequency histogram of the data. Comment on the shape of the distribution. (b) Draw a boxplot of t

> The following data represent the age (in weeks) at which babies first crawl based on a survey of 12 mothers conducted by Essential Baby. (a) Use either Option 1 or Option 2 to verify the requirements for constructing a confidence interval for the populat

> The following data represent the repair cost for a low-impact collision in a simple random sample of mini- and micro-vehicles (such as the Chevrolet Aveo or Mini Cooper). (a) Use either Option 1 or Option 2 to verify the requirements for constructing a c

> A marketing executive for Coca-Cola, Inc., wants to identify television shows that people in the Boston area who typically drink Coke are watching. The executive has a list of all households in the Boston area. Design a sampling method to obtain the indi

> Travelers pay taxes for flying, car rentals, and hotels. The following data represent the total travel tax for a 3-day business trip in 8 randomly selected cities. Note: Chicago travel taxes are the highest in the country at $101.27. A normal probability

> The following data represent the pH of rain for a random sample of 12 rain dates in Tucker County, West Virginia. A normal probability plot suggests the data could come from a population that is normally distributed. A boxplot indicates there are no outl

> A recent Gallup poll asked 1006 Americans, “During the past year, about how many books, either hardcover or paperback, did you read either all or part of the way through?” Results of the survey indicated that / = 13.4 books and s = 16.6 books. Construct

> A Tootsie Pop is a sucker with a candy center. A famous commercial for Tootsie Pops once asked, “How many licks to the center of a Tootsie Pop?” In an attempt to answer this question, Cory Heid of Siena Heights University asked 92 volunteers to count the

> How much time do Americans spend eating or drinking? Suppose for a random sample of 1001 Americans age 15 or older, the mean amount of time spent eating or drinking per day is 1.22 hours with a standard deviation of 0.65 hour. Source: American Time U

> A random sample of 51 fatal crashes in 2017 in which the driver had a positive blood alcohol concentration (BAC) from the National Highway Traffic Safety Administration results in a mean BAC of 0.167 gram per deciliter (g/dL) with a standard deviation of

> Refer to the “Sleeping” results from Problem 22. What could be done to decrease the width of the confidence interval?

> For the “Hours Worked” survey conducted by Gallup in Problem 21, provide two recommendations for decreasing the width of the interval.

> Michael Sullivan, the author of this text, determined the mean amount of weekly screen time spent on his phone was 81.3 minutes. A 95% confidence interval for the mean amount of time spent on his phone weekly has a lower bound of 72.9 minutes. (a) What i

> The trade magazine QSR routinely checks the drive-through service times of fast-food restaurants. A 90% confidence interval that results from examining 607 customers in Taco Bell’s drive-through has a lower bound of 161.5 seconds and an upper bound of 16

> A pharmaceutical company wants to conduct a survey of 30 individuals who have high cholesterol. The company has obtained a list from doctors throughout the country of 6600 individuals who are known to have high cholesterol. Design a sampling method to ob

> A 90% confidence interval for the number of hours that full-time college students sleep during a weekday is lower bound: 7.8 hours and upper bound: 8.8 hours. Which of the following represents a reasonable interpretation of the result? For those that are

> In a survey conducted by the Gallup Organization, 1100 adult Americans were asked how many hours they worked in the previous week. Based on the results, a 95% confidence interval for mean number of hours worked was lower bound: 42.7 hours and upper bound

> A simple random sample of size n is drawn. The sample mean, /, is found to be 35.1, and the sample standard deviation, s, is found to be 8.7. (a) Construct a 90% confidence interval for  if the sample size, n, is 40. (b) Construct a 90% confidence inter

> A simple random sample of size n is drawn. The sample mean, /, is found to be 18.4, and the sample standard deviation, s, is found to be 4.5. (a) Construct a 95% confidence interval for  if the sample size, n, is 35. (b) Construct a 95% confidence inter

> A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, /, is found to be 50, and the sample standard deviation,s, is found to be 8. (a) Construct a 98% confidence interval for  if the sample size, n, i

> A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, /, is found to be 108, and the sample standard deviation, s, is found to be 10. (a) Construct a 96% confidence interval for  if the sample size, n

> Lower bound: 15, upper bound: 35

> Lower bound: 5, upper bound: 23

> Lower bound: 20, upper bound: 30

> Lower bound: 18, upper bound: 24

> The county sheriff wants to determine if a certain highway has a high proportion of speeders traveling on it. Design a sampling method to obtain the individuals in the sample. Be sure to support your choice.

> Number of unpopped kernels in a bag of microwave popcorn

> n = 9; Correlation = 0.997

> n = 13; Correlation = 0.966

> n = 15; Correlation = 0.893

> n = 12; Correlation = 0.987

> (a) Find the t-value such that the area in the right tail is 0.02 with 19 degrees of freedom. (b) Find the t-value such that the area in the right tail is 0.10 with 32 degrees of freedom. (c) Find the t-value such that the area left of the t-value is 0.0

> (a) Find the t-value such that the area in the right tail is 0.10 with 25 degrees of freedom. (b) Find the t-value such that the area in the right tail is 0.05 with 30 degrees of freedom. (c) Find the t-value such that the area left of the t-value is 0.

> The procedure for constructing a confidence interval about a mean is_____ , which means minor departures from normality do not affect the accuracy of the interval.

> True or False: To construct a confidence interval about the mean, the population from which the sample is drawn must be approximately normal.

> Put the following in order from narrowest to widest interval. Assume the sample size and sample proportion is the same for all four confidence intervals. (a) 95% confidence interval (b) 80% confidence interval (c) 99% confidence interval (d) 90% confiden

> If you constructed one hundred 95% confidence intervals based on one hundred different simple random samples of size n, how many of the intervals would you expect to include the unknown parameter? Assume all model requirements are satisfied.

> Target wants to open a new store in the village of Lockport. Before construction, Target’s marketers want to obtain some demographic information regarding the area under consideration. Design a sampling method to obtain the individuals in the sample. Be

> Define each of the following. (a) Point estimate (b) Confidence interval (c) Level of confidence (d) Margin of error

> The 116th House of Representatives of the United States of America has 435 members, of which 106 are women. An alien lands near the U.S. Capitol and treats members of the House as a random sample of the human race. He reports to his superiors that a 95%

> Two researchers, Jaime and Mariya, are each constructing confidence intervals for the proportion of a population who is left-handed. They find the point estimate is 0.13. Each independently constructed a confidence interval based on the point estimate, b

> Katrina wants to estimate the proportion of adult Americans who read at least 10 books last year. To do so, she obtains a simple random sample of 100 adult Americans and constructs a 95% confidence interval. Matthew also wants to estimate the proportion

> Why do polling companies often survey 1060 individuals when they wish to estimate a population proportion with a margin of error of 3% with 95% confidence?

> Explain why quadrupling the sample size causes the margin of error to be cut in half.

> What type of variable is required to construct a confidence interval for a population proportion?

> Explain what “95% confidence” means in a 95% confidence interval.

> The American Society for Microbiology (ASM) and the Soap and Detergent Association (SDA) jointly commissioned two separate studies, both of which were conducted by Harris Interactive. In one of the studies, 1001 adults were interviewed by telephone an

> Alan wants to estimate the proportion of adults who walk to work. In a survey of 10 adults, he finds 1 who walks to work. Explain why a 95% confidence interval using the normal model yields silly results. Then compute and interpret a 95% confidence inter

> Jane wants to estimate the proportion of students on her campus who eat cauliflower. After surveying 20 students, she finds 2 who eat cauliflower. Obtain and interpret a 95% confidence interval for the proportion of students who eat cauliflower on Jane’s

> A Bernoulli random variable is a variable that is either 0 (a failure) or 1 (a success). The probability of success is denoted p. (a) Use a statistical spreadsheet to generate 1000 Bernoulli samples of size n = 20 with p = 0.15. (b) Determine the sample

> CNN polled 702 likely voters immediately preceding the 2018 Arizona senate race. The results of the survey indicated that Kyrsten Sinema had the support of 51% of respondents, while Martha McSally had support of 47%. The poll’s margin of error was 4.4%.

> In a Gallup Poll, 44% of the people polled answered “more strict” to the following question: “Do you feel that the laws covering the sale of firearms should be made more strict, less strict, or kept as they are now?” Suppose the margin of error in the po

> In a Gallup poll, 64% of the people polled answered yes to the following question: “Are you in favor of the death penalty for a person convicted of murder?” The margin of error in the poll was 3%, and the estimate was made with 95% confidence. At least h

> A sociologist wishes to conduct a poll to estimate the percentage of Americans who favor affirmative action programs for women and minorities for admission to colleges and universities. What sample size should be obtained if she wishes the estimate to be

> A television sports commentator wants to estimate the proportion of Americans who follow professional football. What sample size should be obtained if he wants to be within 3 percentage points with 95% confidence if (a) he uses a 2010 estimate of 53% ob

> A school administrator is concerned about the amount of credit-card debt that college students have. She wishes to conduct a poll to estimate the percentage of full-time college students who have credit-card debt of $2000 or more. What size sample should

> A researcher for the U.S. Department of the Treasury wishes to estimate the percentage of Americans who support abolishing the penny. What size sample should be obtained if he wishes the estimate to be within 2 percentage points with 98% confidence if (a

> An urban economist wishes to estimate the proportion of Americans who own their homes. What size sample should be obtained if he wishes the estimate to be within 0.02 with 90% confidence if (a) he uses a 2010 estimate of 0.669 obtained from the U.S. Cens

> The city of Naperville is considering the construction of a new commuter rail station. The city wishes to survey the residents of the city to obtain their opinion regarding the use of tax dollars for this purpose. Design a sampling method to obtain the i

> A researcher wishes to estimate the proportion of households that have broadband Internet access. What size sample should be obtained if she wishes the estimate to be within 0.03 with 99% confidence if (a) she uses a 2009 estimate of 0.635 obtained from

> Go to www.pearsonhighered.com/ sullivanstats to obtain the data file 9_1_34 using the file format of your choice for the version of the text you are using. The data represent the daily (for example, Monday to Tuesday) movement of Johnson & Johnson (JNJ)

> The data set “Tornadoes_2017” located at www.pearsonhighered.com/ sullivanstats contains a variety of variables that were measured for all tornadoes in the United States in 2017. (a) The F scale is used to describe the range of wind speeds of a tornado.

> The Sullivan Statistics Survey I asks, “Would you be willing to pay higher taxes if the tax revenue went directly toward deficit reduction?” Treat the survey respondents as a random sample of adult Americans. Go to www.pearsonhighered.com/sullivanstats t

> In a survey conducted by the marketing agency 11mark, 241 of 1000 adults 19 years of age or older confessed to bringing and using their cell phone every trip to the bathroom (confessions included texting and answering phone calls). (a) What is the sample

> In a survey of 700 community college students, 481 indicated that they have read a book for personal enjoyment during the school year (based on data from the Community College Survey of Student Engagement). (a) Determine a 90% confidence interval for the

> Low levels of testosterone in adult males may be treated using AndroGel 1.62%. In clinical studies of 234 adult males who were being treated with AndroGel 1.62%, it was found that 26 saw their prostate-specific antigen (PSA) elevated. The PSA is a protei

> In a USA Today/Gallup poll, 768 of 1024 randomly selected adult Americans aged 18 or older stated that a candidate’s positions on the issue of family values are extremely or very important in determining their vote for president. (a) Obtain a point estim

> A random sample of 1003 adult Americans was asked, “Do you pretty much think televisions are a necessity or a luxury you could do without?” Of the 1003 adults surveyed, 521 indicated that televisions are a luxury they could do without. (a) Obtain a point

> Relative to other nations, how do fourth-graders in the United States rank in terms of reading and math ability? Are they in the bottom 50% or in the top 50%? In a survey of 700 randomly sampled registered voters in the United States conducted by Conques

> To obtain students’ opinions about proposed changes to course registration procedures, the administration of a small college asked for faculty volunteers who were willing to administer a survey in one of their classes. Twenty-three faculty members volunt

> A survey of 2306 adult Americans aged 18 and older conducted by Harris Interactive found that 417 have donated blood in the past two years. (a) Obtain a point estimate for the population proportion of adult Americans aged 18 and older who have donated bl

> A Gallup poll of 547 adult Americans employed full or part time asked, “Generally speaking, would you say your commute to work is— very stressful, somewhat stressful, not that stressful, or not stressful at all?” Gallup reported that 24% of American work

> A Rasmussen Reports national survey of l000 adult Americans found that 18% dreaded Valentine’s Day. The margin of error for the survey was 4.5 percentage points with 95% confidence. Explain what this means.

> A USA Today/Gallup poll asked l006 adult Americans how much it would bother them to stay in a room on the 13th floor of a hotel. Interestingly, 13% said it would bother them. The margin of error was 3 percentage points with 95% confidence. Which of the f

> In response to the Great Depression, Franklin D. Roosevelt enacted many New Deal policies. One such policy was the enactment of the National Recovery Administration (NRA), which required businesses to agree to wages and prices within their particular ind

> x = 540, n = 900, 96% confidence

> x = 860, n = 1100, 94% confidence

> x = 400, n = 1200, 95% confidence

> x = 120, n = 500, 99% confidence

> x = 80, n = 200, 98% confidence

> The mathematics department at a university wishes to administer a survey to a sample of students taking college algebra. The department is offering 32 sections of college algebra, similar in class size and makeup, with a total of 1280 students. They woul

> x = 30, n = 150, 90% confidence

> Lower bound: 0.853, upper bound: 0.871, n = 10,732

> Lower bound: 0.462, upper bound: 0.509, n = 1680

> Lower bound: 0.051, upper bound: 0.074, n = 1120

> Lower bound: 0.201, upper bound: 0.249, n = 1200

> 92%

> 98%

> 99%

> 90%

> As the level of confidence of a confidence interval increases, the margin of error_____ (increases/decreases). As the sample size used to obtain a confidence interval increases, the margin of error______ (increases/decreases).

> To predict the outcome of a county election, a newspaper obtains a list of all 945,035 registered voters in the county and wants to conduct a systematic sample. (a) Determine k if the sample size is 130. (b) Determine the individuals who will be administ

> True or False: A 95% confidence interval for a population proportion with lower bound 0.45 and upper bound 0.51 means there is a 95% probability the population proportion is between 0.45 and 0.51

> If a sample proportion is 0.55, which of the following could be a 90% confidence interval for the population proportion? Select all that apply. (a) Lower bound: 0.50; Upper bound: 0.60 (b) Lower bound: 0.53; Upper bound: 0.59 (c) Lower bound: 0.52; Upper

> The ___ ____, denoted /, is given by the formula / = _____ , where x is the number of individuals with a specified characteristic in a sample of n individuals.

> In a town of 500 households, 220 have a dog. The population proportion of dog owners in this town (expressed as a decimal) is p =______ .

> The New England Patriots made headlines prior to the 2015 Super Bowl for allegedly playing with underinflated footballs. An underinflated ball is easier to grip, and therefore, less likely to be fumbled. What do the data say? The following data represent

> In this section, we assumed that the sample size was less than 5% of the size of the population. When sampling without replacement from a finite population in which n > 0.05N, the standard deviation of the distribution of / is given by where N is the si

> In Chapter 6, we learned that the proportion of passengers who miss a flight for which they have a reservation is 0.0995. (a) Suppose a flight has 290 reservations. What is the probability that 25 or more passengers will miss the flight? (b) Suppose a fl