We are interested in the mean scores on an exam. A random sample of 36 scores is taken and gives a sample mean of 78. Suppose that we know that the population standard deviation is 3 points. Choices below are given as [lower limit, upper limit]. What is the 90% confidence interval estimate for the population mean exam score?

Question 1 options:

a)	[77.2, 78.8]

b)	[77.4, 78.6]

c)	[77.0, 79.0]

d)	None of the other choices

Question 2 (1 point)

We are interested in the mean scores on an exam. A random sample of 16 scores is taken and gives a sample mean of 78. Suppose that we know that the population standard deviation is 3 points. Choices below are given as [lower limit, upper limit]. What is the 95% confidence interval estimate for the population mean exam score?

Question 2 options:

a)	[77.4, 78.6]

b)	[77.2, 78.8]

c)	[76.5, 79.5]

d)	None of the other choices

Question 3 (1 point)

We are interested in the mean scores on an exam. A random sample of 16 scores is taken and gives a sample mean of 78. Suppose that we know that the exam scores are normally distributed with a population standard deviation of 3 points. Choices below are given as [lower limit, upper limit]. What is the 95% confidence interval estimate for the population mean exam score?

Question 3 options:

a)	[77.4, 78.6]

b)	None of the other choices

c)	[76.5, 79.5]

d)	[77.2, 78.8]

Question 4 (1 point)

Suppose the earnings per share (EPS) for a population of industrial stocks are normally distributed. A random sample of 16 stocks is taken. The sample mean is 1.90 and the sample standard deviation is 0.40. Choices below are given as [lower limit, upper limit]. What is the 99% confidence interval for the average EPS of this population of industrial stocks?

Question 4 options:

a)	[1.61, 2.19]

b)	[1.50, 2.30]

c)	[1.57, 2.23]

d)	None of the other choices

Question 5 (1 point)

Suppose the earnings per share (EPS) for a population of industrial stocks have an unknown distribution. A random sample of 16 stocks is taken. The sample mean is 1.90 and the sample standard deviation is 0.40. Choices below are given as [lower limit, upper limit]. What is the 90% confidence interval for the average EPS of this population of industrial stocks?

Question 5 options:

a)	[1.72, 2.08]

b)	None of the other choices

c)	[1.57, 2.23]

d)	[1.50, 2.30]

Question 6 (1 point)

A financial officer for a company wants to estimate the percent of accounts receivable that are more than 30 days overdue. He surveys 500 accounts and finds that 200 are more than 30 days overdue. What is the 90% confidence interval for the true percent of accounts receivable that are more than 30 days overdue?

Question 6 options:

a)	[35.7%, 44.3%]

b)	None of the other choices

c)	[37.2%, 42.8%]

d)	[36.4%, 43.6%]

Question 7 (1 point)

A business analyst wants to estimate the average monthly expenditure on bread by a family in Montreal. She wants to be 95% confident of her results, and she wants the estimate to be within $1.00 of the actual figure. Choices below are given as [lower limit, upper limit]. The historical standard deviation of monthly bread purchases is $4.00. What is the required sample size to achieve her estimation accuracy?

Question 7 options:

a)

62

b)

63

c)

61

d)

44

Question 8 (1 point)

Hewitt Associates conducted a national survey to determine the extent to which employers are promoting fitness among their employees. One of the questions asked was "Does your company offer on-site exercise classes?" Suppose it was estimated before the study that no more than 30% of the companies would answer yes. How large a sample would Hewitt Associates need in estimating the population proportion to ensure a 95% confidence in the results and to be within 0.03 of the true population proportion?

Question 8 options:

a)

1448

b)

631

c)

897

d)

632

Question 9 (1 point)

Hewitt Associates conducted a national survey to determine the extent to which employers are promoting fitness among their employees. One of the questions asked was "Does your company offer on-site exercise classes?" How large a sample would Hewitt Associates need in estimating the population proportion to ensure a 90% confidence in the results and to be within 0.03 of the true population proportion?

Question 9 options:

a)

752

b)

531

c)

1448

d)

897