Question: Suppose Jack and Diane are each using

> 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

> Consider the homeowners association presented at the beginning of this section. A random sample of 20 households resulted in 15 indicating that they would favor an increase in assessments. Explain why the normal model could not be used to determine if a

> Suppose 21% of all American teens (age 13–17 years) believe in reincarnation. (a) Bob and Alicia both obtain a random sample of 100 American teens and ask each participant to disclose whether they believe in reincarnation or not. Is “belief in reincarnat

> A researcher studying ADHD among teenagers obtains a simple random sample of 100 teenagers aged 13–17 and asks them whether or not they have ever been prescribed medication for ADHD. To say that the distribution of /, the sample proportion of teenagers w

> The human resource department at a certain company wants to conduct a survey regarding worker morale. The department has an alphabetical list of all 4502 employees at the company and wants to conduct a systematic sample. (a) Determine k if the sample siz

> A researcher studying public opinion of proposed Social Security changes obtains a simple random sample of 50 adult Americans and asks them whether or not they support the proposed changes. To say that the distribution of /, the sample proportion of adul

> A shipment of 50,000 transistors arrives at a manufacturing plant. The quality control engineer at the plant obtains a random sample of 500 resistors and will reject the entire shipment if 10 or more of the resistors are defective. Suppose that 4% of the

> Exit polling is a popular technique used to determine the outcome of an election prior to results being tallied. Suppose a referendum to increase funding for education is on the ballot in a large town (voting population over 100,000). An exit poll of 310

> The Pew Research Center recently reported that 18% of women 40–44 years of age have never given birth. Suppose a random sample of 250 adult women 40–44 years of age results in 52 indicating they have never given birth. Explain why this is not necessarily

> According to a study conducted by the Gallup organization, the proportion of Americans who are afraid to fly is 0.10. A random sample of 1100 Americans results in 121 indicating that they are afraid to fly. Explain why this is not necessarily evidence th

> According to creditcard.com, 29% of adults do not own a credit card. (a) Suppose a random sample of 500 adults is asked, “Do you own a credit card?” Describe the sampling distribution of /, the proportion of adults who do not own a credit card. (b) What

> According to a study done by the Pew Research Center, 39% of adult Americans believe that marriage is now obsolete. (a) Suppose a random sample of 500 adult Americans is asked whether marriage is obsolete. Describe the sampling distribution of /, the pro

> According to a study done by the Gallup organization, the proportion of Americans who are satisfied with the way things are going in their lives is 0.82. (a) Suppose a random sample of 100 Americans is asked, “Are you satisfied with the way things are go

> According to a study done by Wakefield Research, the proportion of Americans who can order a meal in a foreign language is 0.47. (a) Suppose a random sample of 200 Americans is asked to disclose whether they can order a meal in a foreign language. Is the

> A simple random sample of size n = 1460 is obtained from a population whose size is N = 1,500,000 and whose population proportion with a specified characteristic is p = 0.42. (a) Describe the sampling distribution of /. (b) What is the probability of obt

> The owner of a private food store is concerned about employee morale. She decides to survey the managers and hourly employees to see if she can learn about work environment and job satisfaction. From the list of workers at the store, obtain a stratified

> A simple random sample of size n = 1000 is obtained from a population whose size is N = 1,000,000 and whose population proportion with a specified characteristic is p = 0.35. (a) Describe the sampling distribution of /. (b) What is the probability of o

> A simple random sample of size n = 200 is obtained from a population whose size is N = 25,000 and whose population proportion with a specified characteristic is p = 0.65. (a) Describe the sampling distribution of /. (b) What is the probability of obtaini

> A simple random sample of size n = 75 is obtained from a population whose size is N = 10,000 and whose population proportion with a specified characteristic is p = 0.8. (a) Describe the sampling distribution of /. (b) What is the probability of obtaining

> n = 1010, p = 0.84

> n = 1000, p = 0.103

> n = 300, p = 0.7

> n = 500, p = 0.4

> What happens to the standard deviation of / as the sample size increases? If the sample size is increased by a factor of 4, what happens to the standard deviation of /?

> Describe the circumstances under which the shape of the sampling distribution of / is approximately normal.

> True or False: The mean of the sampling distribution of / is p.

> The Future Government Club wants to sponsor a panel discussion on the upcoming national election. The club wants to have four of its members lead the panel discussion. To be fair, however, the panel should consist of two Democrats and two Republicans. Fr

> True or False: The population proportion and sample proportion always have the same value.

> True or False: The distribution of the sample mean, /, will be approximately normally distributed if the sample is obtained from a population that is normally distributed, regardless of the sample size.

> The standard deviation of the sampling distribution of / is called the ____ ____of the____.

> Suppose a simple random sample of size is drawn from a large population with mean  and standard deviation . The sampling distribution of / and standard deviation /

> The of the sample mean, /, is the probability distribution of all possible values of the random variable / computed from a sample of size n from a population with mean  and standard deviation 

> A bull market is defined as a market condition in which the price of a security rises for an extended period of time. A bull market in the stock market is often defined as a condition in which a market rises by 20% or more without a 20% decline. The data

> Suppose you want to study the number of hours of sleep full-time college students at your college get each evening. To do so, you obtain a list of full-time students at your college, obtain a simple random sample of ten students, and ask each of them to

> Suppose you want to study the number of hours of sleep you get each evening. To do so, you look at the calendar and randomly select 10 days out of the next 300 days and record the number of hours you sleep. (a) Explain why number of hours of sleep in a n

> For the three probability distributions shown, rank each distribution from lowest to highest in terms of the sample size required for the distribution of the sample mean to be approximately normally distributed. Justify your choice.

> A quality-control expert wishes to obtain a cluster sample by selecting 10 of 795 clusters. She numbers the clusters from 1 to 795. Using Table I from Appendix A, she closes her eyes and drops a pencil on the table. It points to the digit in row 8, colum

> Number on a football player’s jersey

> Without doing any computation, decide which has a higher probability, assuming each sample is from a population that is normally distributed with  = 100 and  = 15. Explain your reasoning. (a) /for a random sample of size n = 10. (b) /for a random sampl

> We assume that we are obtaining simple random samples from infinite populations when obtaining sampling distributions. If the size of the population is finite, we technically need a finite population correction factor. However, if the sample size is smal

> State the Central Limit Theorem.

> Explain what a sampling distribution is.

> In the game of roulette, a wheel consists of 38 slots numbered 0, 00, 1, 2, . . . , 36. (See the photo.) To play the game, a metal ball is spun around the wheel and is allowed to fall into one of the numbered slots. If the number of the slot the ball fal

> Bicycle sharing exists in a variety of cities around the country. Los Angeles has the Metro Bike Share system. Users pick up a bike from one station, go for a ride, and return the bike to any station. Go to www.pearsonhighered.com/sullivanstats and downl

> 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) Draw a relative histogram of the variable “Length.” Describe the shape o

> The following data represent the running lengths (in minutes) of the winners of the Academy Award for Best Picture for the years 2012–2017. (a) Compute the population mean, . (b) List all possible samples with size n = 2. There should be 6C2 = 15 sample

> The following data represent the ages of the winners of the Academy Award for Best Actor for the years 2012–2017. (a) Compute the population mean, . (b) List all possible samples with size n = 2. There should be 6C2 = 15 samples. (c) Construct a samplin

> According to Crown ATM Network, the mean ATM withdrawal is $67. Assume that the standard deviation for withdrawals is $35. (a) Do you think the variable “ATM withdrawal” is normally distributed? If not, what shape would you expect the variable to have? (

> A salesperson obtained a systematic sample of size 20 from a list of 500 clients. To do so, he randomly selected a number from 1 to 25, obtaining the number 16. He included in the sample the 16th client on the list and every 25th client thereafter. List

> The amount of time Americans spend watching television is closely monitored by firms such as AC Nielsen because this helps determine advertising pricing for commercials. (a) Do you think the variable “weekly time spent watching television” would be norma

> Suppose that cars arrive at Burger King’s drive-thru at the rate of 20 cars every hour between 12:00 noon and 1:00 P.M. A random sample of 40 one- hour time periods between 12:00 noon and 1:00 P.M. is selected and has 22.1 as the mean number of cars arri

> The Food and Drug Administration sets Food Defect Action Levels (FDALs) for some of the various foreign substances that inevitably end up in the food we eat and liquids we drink. For example, the FDAL for insect filth in peanut butter is 3 insect fragmen

> The quality-control manager of a Long John Silver’s restaurant wants to analyze the length of time that a car spends at the drive-thru window waiting for an order. It is determined that the mean time spent at the window is 59.3 seconds with a standard de

> The shape of the distribution of the time required to get an oil change at a 10-minute oil-change facility is skewed right. However, records indicate that the mean time for an oil change is 11.4 minutes, and the standard deviation for oil-change time is

> A very good poker player is expected to earn $1 per hand in $100/$200 Texas Hold’em. The standard deviation is approximately $32. (a) What is the probability a very good poker player earns a profit (more than $0) after playing 50 hands in $100/$200 Texas

> The S&P 500 is a collection of 500 stocks of publicly traded companies. Using data obtained from Yahoo! Finance, the monthly rates of return of the S&P 500 since 1950 are approximately normal. The mean rate of return is 0.007233 (0.7233%), and the standa

> The most famous geyser in the world, Old Faithful in Yellowstone National Park, has a mean time between eruptions of 85 minutes. If the interval of time between eruptions is approximately normal with standard deviation 21.25 minutes, answer the following

> The reading speed of second-grade students is approximately normal, with a mean of 90 words per minute (wpm) and a standard deviation of 10 wpm. (a) What is the probability a randomly selected student will read more than 95 words per minute? (b) What is

> The upper leg length of 20- to 29-year-old males is approximately normal with a mean length of 43.7 cm and a standard deviation of 4.2 cm. Source: “Anthropometric Reference Data for Children and Adults: U.S. Population, 1999–2002”; Volume 361, July 7, 20

> 24 Hour Fitness wants to administer a satisfaction survey to its current members. Using its membership roster, the club randomly selects 40 club members and asks them about their level of satisfaction with the club.

> The length of human pregnancies is approximately normal with mean = 266 days and standard deviation = 16 days. (a) What is the probability a randomly selected pregnancy lasts less than 260 days? (b) Suppose a random sample of 20 pregnancies is obtain

> A simple random sample of size n = 20 is obtained from a population with  = 64 and  = 17. (a) What must be true regarding the distribution of the population in order to use the normal model to compute probabilities involving the sample mean? Assuming t

> A simple random sample of size n = 12 is obtained from a population with  = 64 and  = 17. (a) What must be true regarding the distribution of the population in order to use the normal model to compute probabilities involving the sample mean? Assuming t

> A simple random sample of size n = 36 is obtained from a population with  = 64 and  = 18. (a) Describe the sampling distribution of /. (b) What is / (c) What is / (d) What is /

> A simple random sample of size n = 49 is obtained from a population with / (a) Describe the sampling distribution of /. (b) What is / (c) What is / (d) What is /

> Answer the following questions for the sampling distribution of the sample mean shown to the right. (a) What is the value of / (b) What is the value of / (c) If the sample size is n = 9,what is likely true about the shape of the population? (d) If the

> Answer the following questions for the sampling distribution of the sample mean shown to the right. (a) What is the value of / (b) What is the value of / (c) If the sample size is n = 16, what is likely true about the shape of the population? (d) If the

>  = 27, = 6, n = 15

>  = 52, = 10, n = 21

>  = 64,  = 18, n = 36

> To determine his DSL Internet connection speed, Shawn divides up the day into four parts: morning, midday, evening, and late night. He then measures his Internet connection speed at 5 randomly selected times during each part of the day.

> = 80 = 14, n = 49

> A simple random sample of size n = 40 is obtained from a population with  = 50 and  = 4. Does the population need to be normally distributed for the sampling distribution of / to be approximately normally distributed? Why? What is the sampling distribu

> A simple random sample of size n = 10 is obtained from a population that is normally distributed with  = 30 and  = 8. What is the sampling distribution of /?

> True or False: To cut the standard error of the mean in half, the sample size must be doubled.

> True or False: The distribution of the sample mean, /, will be approximately normally distributed if the sample is obtained from a population that is not normally distributed, regardless of the sample size.

> Suppose X is a binomial random variable. To approximate /

> When adding or subtracting 0.5 from x, we are making a correction for_____.

> In a binomial experiment with n trials and probability of success p, if_____ , the binomial random variable X is approximately normal with /

> According to a USA Today “Snapshot,” 3% of Americans surveyed lie frequently. You conduct a survey of 500 college students and find that 20 of them lie frequently. (a) Compute the probability that, in a random sample of 500 college students, at least 20

> In a Pew Research poll, 42% of adult Americans had a positive view of socialism. You conduct a survey of 200 randomly selected students at your school and find that 103 have a positive view of socialism. (a) Approximate the probability that, in a random

> The presider of a guest-lecture series at a university stands outside the auditorium before a lecture begins and hands every fifth person who arrives, beginning with the third, a speaker evaluation survey to be completed and returned at the end of the pr

> According to the Current Population Survey (Internet release date: September 15, 2004), 46% of females between the ages of 18 and 24 years lived at home in 2003. (Unmarried college students living in a dorm are counted as living at home.) Suppose a surve

> According to the Current Population Survey (Internet release date: September 15, 2004), 55% of males between the ages of 18 and 24 years lived at home in 2003. (Unmarried college students living in a dorm are counted as living at home.) Suppose a survey

> According to a study done by Nick Wilson of Otago University Wellington, the probability a randomly selected individual will not cover his or her mouth when sneezing is 0.267. Suppose you sit on a bench in a mall and observe 300 randomly selected individ

> In the Healthy Handwashing Survey conducted by Bradley Corporation, it was found that 64% of adult Americans operate the flusher of toilets in public restrooms with their foot. Suppose you survey a random sample of 740 adult American women aged 18–24 yea