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.
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
2. In some situations sampling may be the only option because the population is inaccessible.
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
3. A population list map directory or other source used to represent the population from which a sample is taken is called the census.
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
4. In a random sampling technique every unit of the population has a randomly varying chance or probability of being included in the sample.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
5. Cluster (or area) sampling is a type of random sampling technique.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
6. Systematic sampling is a type of nonrandom sampling technique.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
7. A major limitation of nonrandom samples is that they are not appropriate for most statistical methods.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
8. The directory or map from which a sample is taken is called the frame.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
9. The two major categories of sampling methods are proportionate and disproportionate sampling.
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
10. If every unit of the population has the same probability of being selected to the sample then the researcher is probably conducting random sampling.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
11. With cluster sampling there is homogeneity within a subgroup or stratum.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
12. If every unit of the population has the same probability of being selected to the sample then the researcher is probably conducting random sampling.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
13. If a researcher selects every kth item from a population of N items then she is likely conducting a stratified random sampling.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
14. If every unit of the population has the same probability of being selected to the sample then the researcher is conducting random sampling.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
15. A nonrandom sampling technique that is similar to stratified random sampling is called quota sampling.
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
16. Nonsampling error occurs when due to chance the sample is not representative of the population.
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
17. A sampling distribution is the distribution of a sample statistic such as the sample mean or sample proportion.
Ans:
Response: See section 7.2 Sampling Distribution of x
Difficulty: Medium
18. The standard deviation of a sampling distribution of the sample means is commonly called the standard error of the mean.
Ans:
Response: See section 7.2 Sampling Distribution of x
Difficulty: Medium
19. The central limit theorem states that if the sample size n is large enough (n 30) the distribution of the sample means is uniformly distributed regardless of the shape of the population.
Ans:
Response: See section 7.2 Sampling Distribution of x
Difficulty: Medium
20. Increasing the sample size causes the numerical value of standard error of the mean to increase.
Ans:
Response: See section 7.2 Sampling Distribution of x
Difficulty: Hard
Multiple Choice
21. Kristen Ashford purchased the subscribers list for Wind Surfing magazine. She plans to survey a sample of the subscribers before using the list in her mail order business. She chooses the first 100 of the 5000 names. Her sample is a _________.
a) simple random sample
b) stratified sample
c) systematic sample
d) convenience sample
e) cluster sample
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
22. Kristen Ashford purchased the subscribers list for Wind Surfing magazine. She plans to survey a sample of the subscribers before using the list in her mail order business. She randomly selects the fourth name as a starting point and then selects every 50th subsequent name (54 104 154 etc.). Her sample is a _________.
a) simple random sample
b) stratified sample
c) systematic sample
d) convenience sample
e) cluster sample
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
23. Kristen Ashford purchased the subscribers list for Wind Surfing magazine. She plans to survey a sample of the subscribers before using the list in her mail order business. The names are numbered consecutively from 1 to 5000. Kristen chooses her sample by selecting four-digit numbers (1 to 5000) 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
24. Pinky Bauer Chief Financial Officer of Harrison Haulers Inc. suspects irregularities in the payroll system. She knows that 2500 payroll vouchers have been issued since January 1 2000 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
25. Pinky Bauer Chief Financial Officer of Harrison Haulers Inc. suspects irregularities in the payroll system. She knows that 2500 payroll vouchers have been issued since January 1 2000 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
26. Financial analyst Larry Potts needs a sample of 100 securities listed on the New York Stock Exchange. In the current issue of the Wall Street Journal 2531 securities are listed in the New York Exchange Composite Transactions an alphabetical listing of all securities traded on the previous business day. Larry uses a table of random numbers to select 100 numbers between 1 and 2531. His sample is a ____________.
a) quota sample
b) simple random sample
c) systematic sample
d) stratified sample
e) cluster sample
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
27. Financial analyst Larry Potts needs a sample of 100 securities listed on the New York Stock Exchange. In the current issue of the Wall Street Journal 2531 securities are listed in the New York Exchange Composite Transactions an alphabetical listing of all 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
28. 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 2531 NYSE securities and AMEX 746 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
29. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
30. 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 each customer at intervals of 20 (9 29 49 etc.). His sample is a __________.
a) convenience sample
b) simple random sample
c) unsystematic sample
d) stratified sample
e) systematic sample
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
31. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
32. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
33. A carload of palletized aluminum castings has arrived at Mansfield Motor Manufacturers. The car contains 1000 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
34. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 1000 bundles of 50 rods each. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Medium
35. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
36. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
37. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
38. 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
Ans:
Response: See section 7.1 Sampling
Difficulty: Easy
39. 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
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
40. According to the central limit theorem if a sample of size 64 is drawn from a population with a mean of 56 the mean of all sample means would equal _______.
a) 7.00
b) 56.00
c) 64.00
d) 0.875
e) 128.00
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
41. According to the central limit theorem if a sample of size 81 is drawn from a population with a standard deviation of 72 the standard deviation of the distribution of the sample means would equal _______.
a) 8
b) 9
c) 7.2
d) 0.875
e) 128.00
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
42. 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
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
43. 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
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
44. Increasing the sample size causes the sampling distribution of to ________.
a) shift to the right
b) shift to the left
c) have more dispersion
d) have less dispersion
e) stay unchanged
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
45. According to the central limit theorem for samples of size 64 drawn from a population with = 800 and = 56 the mean of the sampling distribution of sample means would equal _______.
a) 7
b) 8
c) 100
d) 800
e) 80
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
46. According to the central limit theorem for samples of size 64 drawn from a population with = 800 and = 56 the standard deviation of the sampling distribution of sample means would equal _______.
a) 7
b) 8
c) 100
d) 800
e) 80
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
47. According to the central limit theorem for samples of size 169 drawn from a population with = 1014 and = 65 the mean of the sampling distribution of sample means would equal _______.
a) 1014
b) 65
c) 5
d) 6
e) 3
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
48. According to the central limit theorem for samples of size 169 drawn from a population with = 1014 and = 65 the standard deviation of the sampling distribution of sample means would equal _______.
a) 1014
b) 65
c) 15
d) 6
e) 5
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Easy
49. Suppose a population has a mean of 90 and a standard deviation of 28. If a random sample of size 49 is drawn from the population the probability of drawing a sample with a mean of more than 95 is _______.
a) 0.1056
b) 0.3944
c) 0.4286
d) 0.8944
e) 1.0000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
50. Suppose a population has a mean of 90 and a standard deviation of 28. If a random sample of size 49 is drawn from the population the probability of drawing a sample with a mean of less than 84 is _______.
a) 0.9332
b) 0.0668
c) 0.4332
d) 0.8664
e) 1.0000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
51. Suppose a population has a mean of 90 and a standard deviation of 28. If a random sample of size 49 is drawn from the population the probability of drawing a sample with a mean between 85 and 95 is _______.
a) 0.1056
b) 0.3944
c) 0.7888
d) 0.2112
e) 0.5000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
52. Suppose a population has a mean of 90 and a standard deviation of 28. If a random sample of size 49 is drawn from the population the probability of drawing a sample with a mean between 80 and 100 is _______.
a) 0.9876
b) 0.0124
c) 0.4938
d) 0.0062
e) 1.0000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
53. 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 _______.
a) 0.0139
b) 0.4861
c) 0.4878
d) 0.0122
e) 0.5000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
54. 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 _______.
a) 0.9756
b) 0.0244
c) 0.0278
d) 0.9722
e) 1.0000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
55. 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 _______.
a) 0.3413
b) 0.6826
c) 0.8413
d) 0.1587
e) 0.9875
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
56. Suppose a population has a mean of 450 and a variance of 900. If a random sample is size 100 is drawn from the population the probability that the sample mean is between 448 and 453 is _______.
a) 0.4972
b) 0.6826
c) 0.4101
d) 0.5899
e) 0.9878
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
57. Suppose a population has a mean of 870 and a variance of 1600. If a random sample is size 64 is drawn from the population the probability that the sample mean is between 860 and 875 is _______.
a) 0.9544
b) 0.6826
c) 0.8785
d) 0.5899
e) 0.8185
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
58. Suppose a population has a mean of 870 and a variance of 8100. If a random sample is size 36 is drawn from the population the probability that the sample mean is between 840 and 900 is _______.
a) 0.9544
b) 0.6826
c) 0.8185
d) 0.5899
e) 0.0897
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
59. 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 ________.
a) 0.4772
b) 0.0228
c) 0.9772
d) 0.9544
e) 1.0000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
60. 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 ________.
a) 0.4772
b) 0.0228
c) 0.9072
d) 0.9544
e) 0.9772
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
61. 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
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
62. 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 ________.
a) 0.9974
b) 0.4987
c) 0.9772
d) 0.4772
e) 0.5000
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
63. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 50000 rods. Claude Ong manager of Quality Assurance directs his crew 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
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
64. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 50000 rods. Claude Ong manager of Quality Assurance directs his crew 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 _____________.
a) 0.9974
b) 0.0026
c) 0.4987
d) 0.0013
e) 0.0030
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
65. A carload of steel rods has arrived at Cybermatic Construction Company. The car contains 50000 rods. Claude Ong manager of Quality Assurance directs his crew 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 ____________.
a) 0.9925
b) 0.9974
c) 0.9876
d) 0.9544
e) 0.9044
Ans:
Response: See section 7.2 Sampling Distribution of
Difficulty: Medium
66. Suppose 40% of the population possess a given characteristic. If a random sample of size 300 is drawn from the population then the probability that 44% or fewer of the samples possess the characteristic is _______.
a) 0.0793
b) 0.4207
c) 0.9207
d) 0.9900
e) 1.0000
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Medium
67. Suppose 30% of a population possess a given characteristic. If a random sample of size 1200 is drawn from the population then the probability that less than 348 possess that characteristic is _______.
a) 0.2236
b) 0.2764
c) 0.2900
d) 0.7764
e) 0.3336
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Medium
68. If the population proportion is 0.90 and a sample of size 64 is taken what is 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
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
69. If the population proportion is 0.90 and a sample of size 64 is taken what is 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
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
70. Suppose 40% of all college students have a computer at home and a sample of 64 is taken. What is 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
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
71. Suppose 40% of all college students have a computer at home and a sample of 100 is taken. What is 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
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
72. Pinky Bauer Chief Financial Officer of Harrison Haulers Inc. suspects irregularities in the payroll system. If 10% of the 5000 payroll vouchers issued since January 1 2000 have irregularities the probability that Pinky’s random sample of 200 vouchers will have a sample proportion greater than .06 is ___________.
a) 0.4706
b) 0.9706
c) 0.0588
d) 0.9412
e) 0.9876
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
73. Pinky Bauer Chief Financial Officer of Harrison Haulers Inc. suspects irregularities in the payroll system. If 10% of the 5000 payroll vouchers issued since January 1 2000 have irregularities the probability that Pinky’s random sample of 200 vouchers will have a sample proportion of between .06 and .14 is ___________.
a) 0.4706
b) 0.9706
c) 0.0588
d) 0.9412
e) 0.8765
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
74. 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 ___________.
a) 0.9232
b) 0.0768
c) 0.4616
d) 0.0384
e) 0.8974
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard
75. 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 ___________.
a) 0.9232
b) 0.0768
c) 0.4616
d) 0.0384
e) 0.8976
Ans:
Response: See section 7.3 Sampling Distribution of
Difficulty: Hard