Test Bank Sampling And Sampling Distributions Chapter 7 nan

File: Ch07, Chapter 7: Sampling and Sampling Distributions

True/False

1. Saving time and money are reasons to take a sample rather than do a census.

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

2. In some situations, sampling may be the only option because the population is inaccessible.

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

3. A population list, map, directory, or other source used to represent the population and from which a sample is taken, is called a frame.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

4. In a random sampling technique, every unit of the population has a randomly varying chance or probability of being included in the sample.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling, which include simple, stratified, systematic, and cluster random sampling; and convenience, judgment, quota, and snowball nonrandom sampling, by assessing the advantages associated with each.

5. Cluster (or area) sampling is a type of random sampling technique.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

6. Systematic sampling is a type of random sampling technique.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

7. A major limitation of nonrandom samples is that they are not appropriate for most statistical methods.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

8. The directory or map from which a sample is taken is called the census.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

9. The two major categories of sampling methods are proportionate and disproportionate sampling.

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

10. If every unit of the population has the same probability of being selected for the sample, then the researcher is probably conducting random sampling.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

11. With cluster sampling, there is homogeneity within a subgroup or stratum.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

12. If a researcher selects every k^th item from a population of N items, then she is likely conducting a systematic random sampling.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

13. If a researcher wants to study all students in their university and includes only those students in the researcher’s class, then the researcher is conducting convenience sampling.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

14. A nonrandom sampling technique that is similar to stratified random sampling is called quota sampling.

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

15. Sampling errors cannot by determined objectively for nonrandom sampling techniques.

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

16. A sampling distribution is the distribution of a sample statistic such as the sample mean or sample proportion.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

17. The standard deviation of a sampling distribution of the sample means is commonly called the standard error of the mean.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

18. The central limit theorem states that if the sample size, n, is large enough (n ≥20), the distribution of the sample means is normally distributed regardless of the shape of the population.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

19. Increasing the sample size causes the numerical value of standard error of the sample means to increase.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

20. The mean of the sample means is the same as the mean of the population

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

21. If the population is normally distributed, the sample means of size n=5 are normally

distributed.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

22. The sampling distribution of the sample means is close to the normal distribution only if the distribution of the population is close to normal.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

23. The sampling distribution of the sample means is less variable than the population distribution.

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

24. The sampling distribution of is close to normal provided that n≥30.

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

25. The sampling distribution of has a mean equal to the square root of the population

proportion p.

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

26. Suppose 90% of students in some specific college have a computer at home and a sample of 40 students is taken. The probability that more than 30 of those in the sample have a computer at home can be approximated using the normal approximation.

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

Multiple Choice

27. Paige DeMarco is the Vice President for University Advancement at State University. She is responsible for the capital campaign to raise money for the new student services building. Paige selects the first 100 alumni listed on a web-based social networking site for State University. She intends to contact these individuals regarding possible donations. Her sample is a _________.

a) simple random sample

b) stratified sample

c) systematic sample

d) convenience sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

28. Paige DeMarco is the Vice President for University Advancement at State University. She is responsible for the capital campaign to raise money for the new student services building. Paige plans to target alumni and acquires her sampling frame from the State University Office of Alumni Relations. She intends to contact these individuals regarding possible donations. She randomly selects the sixth name as a starting point and then selects every 100th subsequent name (106, 206, 306, etc.). Her sample is a _________.
a) simple random sample

b) stratified sample

c) systematic sample

d) convenience sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

29. Paige DeMarco is the Vice President for University Advancement at State University. She is responsible for the capital campaign to raise money for the new student services building. Paige plans to target alumni and acquires her sampling frame from the State University Office of Alumni Relations. She intends to contact these individuals regarding possible donations. Paige chooses her sample by selecting six-digit numbers (1 to 150,000) from a random number table. Her sample is a _________.

a) simple random sample

b) stratified sample

c) systematic sample

d) convenience sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

30. Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in the payroll system. She knows that 2,500 payroll vouchers have been issued since January 1, 2018, and her staff doesn't have time to inspect each voucher. So, she orders her staff to inspect the last 200 vouchers. Her sample is a ___________.

a) stratified sample

b) simple random sample

c) convenience sample

d) systematic sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

31. Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in the payroll system. She knows that 2,500 payroll vouchers have been issued since January 1, 2018, and her staff doesn't have time to inspect each voucher. So, she randomly selects 53 as a starting point and orders her staff to inspect the 53rd voucher and each voucher at an increment of 100 (53, 153, 253, etc.). Her sample is a ___________.

a) stratified sample

b) simple random sample

c) convenience sample

d) cluster sample

e) systematic sample

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

32. Financial analyst Larry Potts needs a sample of 100 securities listed on the New York Stock Exchange. The current issue of the Wall Street Journal has an alphabetical list of the 2,531 securities traded on the previous business day. Larry uses a table of random numbers to select 100 numbers between 1 and 2,531. His sample is a ____________.

a) quota sample

b) simple random sample

c) systematic sample

d) stratified sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

33. Financial analyst Larry Potts needs a sample of 100 securities listed on the New York Stock Exchange. The current issue of the Wall Street Journal has an alphabetical list of the 2,531 securities traded on the previous business day. Larry randomly selects the 7th security as a starting point, and selects every 25th security thereafter (7, 32, 57, etc.). His sample is a ____________.

a) quota sample

b) simple random sample

c) stratified sample

d) systematic sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

34. Financial analyst Larry Potts needs a sample of 100 securities listed on either the New York Stock Exchange (NYSE) or the American Stock Exchange (AMEX). According to the Wall Street Journal's "Stock Market Data Bank," 2,531 NYSE securities and 746 AMEX securities were traded on the previous business day. Larry directs his staff to randomly select 77 NYSE and 23 AMEX securities. His sample is a ____________.

a) disproportionate systematic sample

b) disproportionate stratified sample

c) proportionate stratified sample

d) proportionate systematic sample

e) proportionate cluster sampling

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

35. On Saturdays, cars arrive at David Zebda's Scrub and Shine Car Wash at the rate of 80 cars per hour during the ten-hour shift. David wants a sample of 40 Saturday customers to answer the long version of his quality service questionnaire. He instructs the Saturday crew to select the first 40 customers. His sample is a __________.

a) convenience sample

b) simple random sample

c) systematic sample

d) stratified sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

36. On Saturdays, cars arrive at David Zebda's Scrub and Shine Car Wash at the rate of 80 cars per hour during the ten-hour shift. David wants a sample of 40 Saturday customers to answer the long version of his quality service questionnaire. He randomly selects 9 as a starting point and instructs the crew to select the 9th customer and every 20^th customer thereafter (9, 29, 49, etc.). His sample is a __________.

a) convenience sample

b) simple random sample

c) unsystematic sample

d) stratified sample

e) systematic sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

37. Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers. Accordingly, he plans a sample of waiting times for walk-in customers. Albert instructs his staff to record the waiting times for the first 45 walk-in customers arriving after the noon hour. Albert's sample is a ________.

a) simple random sample

b) systematic sample

c) convenience sample

d) stratified sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

38. Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers. Accordingly, he plans a sample of waiting times for walk-in customers. Albert randomly selects 4 as a starting point and instructs his staff to record the waiting times for the 4th walk-in customer and every 10th customer thereafter (4, 14, 24, etc.). Albert's sample is a ________.

a) simple random sample

b) cluster sample

c) convenience sample

d) stratified sample

e) systematic sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

39. A carload of various palletized aluminum castings has arrived at Mansfield Motor Manufacturers. The car contains 1,000 pallets of 100 castings each. Mario Munoz, Manager of Quality Assurance, directs the receiving crew to deliver the 127th and 869th pallets to his crew for 100% inspection. Mario randomly selected 127 and 869 from a table of random numbers. Mario's sample of 200 castings is a _____________.

a) simple random sample

b) systematic sample

c) stratified sample

d) cluster sample

e) convenience sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

40. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 1,000 bundles of 50 rods of various sizes. Claude Ong, Manager of Quality Assurance, directs the receiving crew to deliver the 63rd and 458th bundles to his crew for 100% inspection. Claude randomly selected 63 and 458 from a table of random numbers. Claude's sample of 100 rods is a _____________.

a) cluster sample

b) simple random sample

c) quota sample

d) systematic sample

e) stratified sample

Response: See section 7.1 Sampling

Difficulty: Medium

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

41. Abel Alonzo, Director of Human Resources, is exploring employee absenteeism at the Harrison Haulers Plant. Abel knows that absenteeism varies significantly between departments. For example, workers in the wood shop are absent more than those in the tuning department and the size of the departments ranges from 40 to 120 workers. He orders a random sample of 10 workers from each of the six departments. Abel's sample is a ________________.

a) proportionate systematic sample

b) proportionate stratified sample

c) disproportionate systematic sample

d) disproportionate stratified sample

e) proportionate cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

42. Abel Alonzo, Director of Human Resources, is exploring employee absenteeism at the Harrison Haulers Plant. Abel knows that absenteeism varies significantly between departments. For example, workers in the wood shop are absent more than those in the tuning department and the size of the departments ranges from 40 to 120 workers. He orders a random sample of 10% of the workers from each of the six departments. Abel's sample is a ________________.

a) proportionate systematic sample

b) proportionate stratified sample

c) disproportionate systematic sample

d) disproportionate stratified sample

e) proportionate cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

43. Catherine Chao, Director of Marketing Research, needs a sample of households to participate in the testing of a new toothpaste package. She chooses thirty-six of her closest friends. Catherine's sample is a _____________.

a) cluster sample

b) convenience sample

c) quota sample

d) systematic sample

e) random sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

44. Catherine Chao, Director of Marketing Research, needs a sample of households to participate in the testing of a new toothpaste package. She directs the seven members of her staff to find five households each. Catherine's sample is a _____________.

a) cluster sample

b) proportionate stratified sample

c) quota sample

d) disproportionate stratified sample

e) simple random sample

Response: See section 7.1 Sampling

Difficulty: Easy

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

45. According to the central limit theorem, if a sample of size 100 is drawn from a population with a mean of 80, the mean of all sample means would equal _______.

a) 0.80

b) 8

c) 80

d) 100

e) 120

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

46. According to the central limit theorem, if a sample of size 56 is drawn from a population with a mean of 16, the mean of all sample means would equal _______.

a) 56

b) 16

c) 7.5

d) 44.0

e) 196

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

47. According to the central limit theorem, if a sample of size 56 is drawn from a population with a standard deviation of 14, the standard deviation of the distribution of the sample means would equal _______.

a) 14

b) 1.87

c) 3.5

d) 0.25

e) 3.74

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

48. According to the central limit theorem, if a sample of size 100 is drawn from a population with a standard deviation of 80, the standard deviation of sample means would equal _______.

a) 0.80

b) 8

c) 80

d) 800

e) 0.080

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

49. According to the central limit theorem, if a sample of size 64 is drawn from a population with a standard deviation of 80, the standard deviation of sample means would equal _______.

a) 10.000

b) 1.250

c) 0.125

d) 0.800

e) 0.080

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

50. Decreasing the sample size causes the sampling distribution of x̄ to ________.

a) shift to the right

b) shift to the left

c) have more dispersion

d) have less dispersion

e) stay unchanged

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

51. According to the central limit theorem, for samples of size 64 drawn from a population with μ = 800 and σ= 56, the mean of the sampling distribution of sample means would equal _______.

a) 7

b) 8

c) 100

d) 800

e) 80

Response: See section 7.2 Sampling Distribution of

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

52. According to the central limit theorem, for samples of size 64 drawn from a population with μ = 800 and σ = 56, the standard deviation of the sampling distribution of sample means would equal _______.

a) 7

b) 8

c) 100

d) 800

e) 80

Response: See section 7.2 Sampling Distribution of

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

53. According to the central limit theorem, for samples of size 169 drawn from a population with μ = 1,014 and σ = 65, the mean of the sampling distribution of sample means would equal _______.

a) 1,014

b) 65

c) 5

d) 6

e) 3

Response: See section 7.2 Sampling Distribution of

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

54. According to the central limit theorem, for samples of size 169 drawn from a population with μ = 1,014 and σ = 65, the standard deviation of the sampling distribution of sample means would equal _______.

a) 1,014

b) 65

c) 15

d) 6

e) 5

Response: See section 7.2 Sampling Distribution of

Difficulty: Easy

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

55. Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18. If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of more than $115 is closest to _______.

a) 0.9738

b) 0.4738

c) 0.0262

d) 0.6103

e) 0.1103

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

56. Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18. If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a mean of less than $92 is closest to _______.

a) 0.3400

b) 0.1600

c) 0.0000

d) 1.0000

e) 0.7000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

57. Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18. If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a sample mean between $100 and $115 is closest to _______.

a) 0.9738

b) 0.4738

c) 0.0262

d) 0.6103

e) 0.1103

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

58. Suppose the population of all public Universities shows the annual parking fee per student is normally distributed with a mean of $110 with a standard deviation of $18. If a random sample of size 49 is drawn from the population, the probability of drawing a sample with a sample mean between $112 and $115 is closest to _______.

a) 0.9738

b) 0.7777

c) 0.7823

d) 0.1915

e) 1.7561

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

59. Suppose a population has a mean of 400 and a standard deviation of 24. If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean of more than 404.5 is closest to _______.

a) 0.0139

b) 0.4861

c) 0.4878

d) 0.0122

e) 0.5000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

60. Suppose a population has a mean of 400 and a standard deviation of 24. If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean between 395.5 and 404.5 is closest to _______.

a) 0.9756

b) 0.0244

c) 0.0278

d) 0.9722

e) 1.0000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

61. Suppose a population has a mean of 400 and a standard deviation of 24. If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean less than 402 is closest to _______.

a) 0.3413

b) 0.6826

c) 0.8413

d) 0.1587

e) 0.9875

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

62. Suppose a population has a mean of 450 and a variance of 900. If a random sample of size 100 is drawn from the population, the probability that the sample mean is between 448 and 453 is closest to _______.

a) 0.4972

b) 0.6826

c) 0.4101

d) 0.5899

e) 0.9878

Response: See section 7.2 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

63. Suppose a population has a mean of 870 and a variance of 1,600. If a random sample of size 64 is drawn from the population, the probability that the sample mean is between 860 and 875 is closest to _______.

a) 0.9544

b) 0.6826

c) 0.8785

d) 0.5899

e) 0.8185

Response: See section 7.2 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

64. Suppose a population has a mean of 870 and a variance of 8,100. If a random sample of size 36 is drawn from the population, the probability that the sample mean is between 840 and 900 is closest to _______.

a) 0.9544

b) 0.6826

c) 0.8185

d) 0.5899

e) 0.0897

Response: See section 7.2 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

65. Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers. Accordingly, he plans a sample of waiting times for walk-in customers. If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean less than 14 minutes is closest to________.

a) 0.4772

b) 0.0228

c) 0.9772

d) 0.9544

e) 1.0000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

66. Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers. Accordingly, he plans a sample of waiting times for walk-in customers. If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean less than 16 minutes is closest to ________.

a) 0.4772

b) 0.0228

c) 0.9072

d) 0.9544

e) 0.9772

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

67. Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers. Accordingly, he plans a sample of waiting times for walk-in customers. If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean less than 15 minutes is ________.

a) 0.5000

b) 0.0228

c) 0.9072

d) 0.9544

e) 1.0000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

68. Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers. Accordingly, he plans a sample of waiting times for walk-in customers. If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean between 13.5 and 16.5 minutes is closest to ________.

a) 0.9974

b) 0.4987

c) 0.9772

d) 0.4772

e) 0.5000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

69. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 50,000 rods. Claude Ong, Manager of Quality Assurance, directs his crew to measure the lengths of 100 randomly selected rods. If the population of rods has a mean length of 120 inches and a standard deviation of 0.05 inch, the probability that Claude's sample has a mean greater than 120.0125 inches is _____________.

a) 0.0124

b) 0.0062

c) 0.4938

d) 0.9752

e) 1.0000

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

70. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 50,000 rods. Claude Ong, manager of Quality Assurance, directs his crew to measure the lengths of 100 randomly selected rods. If the population of rods have a mean length of 120 inches and a standard deviation of 0.05 inch, the probability that Claude's sample has a mean less than 119.985 inches is closest to _____________.

a) 0.9974

b) 0.0026

c) 0.4987

d) 0.0013

e) 0.0030

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

71. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 50,000 rods. Claude Ong, manager of Quality Assurance, directs his crew to measure the lengths of 100 randomly selected rods. If the population of rods has a mean length of 120 inches and a standard deviation of 0.05 inch, the probability that Claude's sample has a mean between 119.985 and 120.0125 inches is closest to ____________.

a) 0.9925

b) 0.9974

c) 0.9876

d) 0.9544

e) 0.9044

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

72. A random sample of size 100 is drawn from a population with a standard deviation of 10. If only 5% of the time a sample mean greater than 20 is obtained, the mean of the population is closest to ______

a) 18.35

b) 16.25

c) 17.2

d) 20

e) 19

Response: See section 7.2 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

73. Suppose 40% of the population of pre-teens have a TV in their bedroom. If a random sample of 500 pre-teens is drawn from the population, then the probability that 44% or fewer of the pre-teens have a TV in their bedroom is closest to _______.

a) 0.9664

b) 0.4644

c) 0.0336

d) 0.0400

e) 0.9600

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

74. Suppose 40% of the population of pre-teens have a TV in their bedroom. If a random sample

of 500 pre-teens is drawn from the population, then the probability that 44% or more of the pre-teens have a TV in their bedroom is _______.

a) 0.9664

b) 0.4644

c) 0.0336

d) 0.0400
e) 0.9600

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

75. Suppose 40% of the population of pre-teens have a TV in their bedroom. If a random sample

of 500 pre-teens is drawn from the population, then the probability that between 36% and 44% of the pre-teens have a TV in their bedroom is closest to _______.
a) 0.9664

b) 0.4644

c) 0.0336

d) 0.9328
e) 0.0712

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

76. Suppose 30% of the U.S. population has green eyes. If a random sample of size 1200 U.S. citizens is drawn, then the probability that less than 348 U.S. citizens have green eyes is _______.

a) 0.2236

b) 0.2764

c) 0.2900

d) 0.7764

e) 0.3336

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

77. If the population proportion is 0.90 and a sample of size 64 is taken, which is closest to the probability that the sample proportion is less than 0.88?

a) 0.2019

b) 0.2981

c) 0.5300

d) 0.7019

e) 0.7899

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

78. If the population proportion is 0.90 and a sample of size 64 is taken, which is closest to the probability that the sample proportion is more than 0.89?

a) 0.1064

b) 0.2700

c) 0.3936

d) 0.6064

e) 0.9000

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

79. Suppose 40% of all college students have a computer at home and a sample of 64 is taken. Which is closest to the probability that more than 30 of those in the sample have a computer at home?

a) 0.3686

b) 0.1314

c) 0.8686

d) 0.6314

e) 0.1343

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

80. Suppose 40% of all college students have a computer at home and a sample of 100 is taken. Which is closest to the probability that more than 50 of those in the sample have a computer at home?

a) 0.4793

b) 0.9793

c) 0.0207

d) 0.5207

e) 0.6754

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

81. Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in the payroll system. If 10% of the 5,000 payroll vouchers issued since January 1, 2018, have irregularities, the probability that Pinky's random sample of 200 vouchers will have a sample proportion greater than .06 is closest to ___________.

a) 0.4706

b) 0.9706

c) 0.0588

d) 0.9412

e) 0.9876

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

82. Pinky Bauer, Chief Financial Officer of Harrison Haulers, Inc., suspects irregularities in the payroll system. If 10% of the 5,000 payroll vouchers issued since January 1, 2018, have irregularities, the probability that Pinky's random sample of 200 vouchers will have a sample proportion of between .06 and .14 is closest to ___________.

a) 0.4706

b) 0.9706

c) 0.0588

d) 0.9412

e) 0.8765

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

83. Catherine Chao, Director of Marketing Research, needs a sample of Kansas City households to participate in the testing of a new toothpaste package. If 40% of the households in Kansas City prefer the new package, the probability that Catherine's random sample of 300 households will have a sample proportion greater than 0.45 is closest to ___________.

a) 0.9232

b) 0.0768

c) 0.4616

d) 0.0384

e) 0.8974

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

84. Catherine Chao, Director of Marketing Research, needs a sample of Kansas City households to participate in the testing of a new toothpaste package. If 40% of the households in Kansas City prefer the new package, the probability that Catherine's random sample of 300 households will have a sample proportion between 0.35 and 0.45 is closest to ___________.

a) 0.9232

b) 0.0768

c) 0.4616

d) 0.0384

e) 0.8976

Response: See section 7.3 Sampling Distribution of

Difficulty: Hard

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

85. In an instant lottery, your chance of winning is 0.1. If you play the lottery 100 times and outcomes are independent, the probability that you win at least 15 percent of the time is closest to __________.

a) 0.4933

b) 0.5

c) .15

d) 0.0478

e) 0.9213

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

86. Suppose 65% of all college students have a laptop computer at home and a sample of 150 students is taken. The mean of the sampling distribution of is

a) 0.65

b) 6.5

c) 97.5

d) 0.975

e) 15.0

Response: See section 7.3 Sampling Distribution of

Difficulty: Easy

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

87. Suppose 65% of all college students have a laptop computer at home and a sample of 150 is taken. The standard deviation of the sampling distribution of is

a) 0.0015

b) 0.0389

c) 0.6500

d) 0.4769

e) 0.0477

Response: See section 7.3 Sampling Distribution of

Difficulty: Medium

Learning Objective: 7.3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.

88. Alice Zhong is the VP of Operations at Pearl Financial Services. She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago. For this purpose, she instructs her staff to prepare a questionnaire and send it to any IP address that accesses the company’s website from 8 a.m. to 9 a.m. during each day of the next four weeks. This is an example of ______.

a) simple random sample

b) systematic sample

c) convenience sample

d) stratified sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

89. Alice Zhong is the VP of Operations at Pearl Financial Services. She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago. For this purpose, she instructs her staff to prepare a questionnaire and send it to the first 200 clients in their alphabetical list of active clients. This is an example of ______.

a) simple random sample

b) systematic sample

c) convenience sample

d) stratified sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Easy

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

90. Alice Zhong is the VP of Operations at Pearl Financial Services. She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago. For this purpose, she uses random five-digits numbers from the website random.org (which offers true random numbers on the Internet). This is an example of ______.

a) simple random sample

b) systematic sample

c) convenience sample

d) stratified sample

e) cluster sample

Response: See section 7.1 Sampling

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

91. Alice Zhong is the VP of Operations at Pearl Financial Services. She wants to measure customer satisfaction after a new website and other changes were introduced a few months ago. 28% of clients are from the healthcare industry, 35% are manufacturing companies, 27% are financial firms, and 7% are construction companies. For this purpose, she gets random five-digits numbers from the website random.org (which offers true random numbers on the Internet). Then she uses these numbers to select 140 random clients from the healthcare sector, 175 from the manufacturing sector, 135 from the manufacturing sector, and 35 from the construction sector. This is an example of ______.

a) disproportionate systematic sample

b) disproportionate stratified sample

c) proportionate stratified sample

d) proportionate systematic sample

e) proportionate cluster sampling

Response: See section 7.1 Sampling

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7.1: Contrast sampling to census and differentiate among different methods of sampling by assessing the advantages associated with each.

92. If random variable X is distributed according to a uniform distribution between 0 and 1 (X ~ U[0, 1]), and you take a random sample of size 35, what is the probability that the sample mean will fall between 0.48 and 0.55?

a) 0.98

b) 0.51

c) 0.76

d) 0.27

e) 0.07

Response: See section 7.2 Sampling Distribution of x̄.

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7. 2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

93. If random variable X is distributed according to a uniform distribution between 0 and 1 (X ~ U[0, 1]), and 100 random samples of sizes 35–40 were taken, the sum of the sample means would be ______.

a) 50.0

b) 37.5

c) 0.50

d) 0.38

e) 0.005

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7. 2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

94. If random variable X is distributed according to a uniform distribution between 0 and 1 (X ~ U[0, 1]), and 100 random samples of sizes 35–40 were taken, the standard deviation of the sample means would be ______.

a) undetermined; there is not enough information to answer

b) between 0.0142 and 0.0151

c) between 0.0456 and 0.0488

d) between 0.0122 and 0.0131

e) between 0.0466 and 0.0498

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7. 2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

95. The employees in certain division of Cybertronics Inc. need to complete a certification online. On average, it takes 20 hours to complete the coursework and successfully pass all tests, with a standard deviation of 6 hours. If you select a random sample of size 30, the probability that the employees in your sample have taken, on average, more than 20.5 hours is ______.

a) 0.47

b) 0.45

c) 0.41

d) 0.32

e) 0.01

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7. 2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

96. Certain transportation company has a fleet of 210 vehicles. The average age of the vehicles is 4.25 years, with a standard deviation of 18 months. In a random sample of 40 vehicles, what is the probability that the average age of vehicles in the sample will be less than 4 years?

a) 0.146

b) 0.163

c) 0.180

d) 0.197

e) 0.214

Response: See section 7.2 Sampling Distribution of x̄

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7. 2: Describe the distribution of a sample’s mean using the central limit theorem, correcting for a finite population if necessary.

97. In Norway, approximately 22% of vehicles are electric vehicles. Which is closest to the probability of randomly selecting 250 cars and finding out that 60 or more are electric?

a) 0.233

b) 0.223

c) 0.213

d) 0.203

e) 0.193

Response: See section 7.3 Sampling Distribution of p̂

Difficulty: Medium

AACSB: Reflective thinking

Bloom’s level: Application

Learning Objective: 7. 3: Describe the distribution of a sample’s proportion using the z formula for sample proportions.