Question 1

We are interested in selecting a sample from a population of size 4,000 in order to develop an approximate 95% confidence interval estimate of the population mean.A pilot study has resulted in a standard deviation of 600.What should be the sample size if we do not want the sampling error to exceed 200?

Accepted Answer

The answer of We are interested in selecting a sample...

Question 2

A sample of 5 clusters is to be taken from a population with N = 30 clusters and M = 300 elements in the population.The values of M_i and X_i for each cluster are shown below. a.Determine the point estimate of the population mean. b.Determine the standard error of the mean. c.Develop a 95% confidence interval for the population mean. d.Determine the point estimator of the population total. e.Approximate a 95% confidence interval estimate of the population total.

Accepted Answer

The answer of A sample of 5 clusters is to...

Question 3

From a population of 2000 accounts receivable,a simple random sample of 120 accounts is selected.Thirty-six of the accounts in the sample were overdue.
a.Estimate the standard error of the proportion of the overdue accounts.
b.Develop an approximate 95% confidence interval for the proportion of overdue accounts in the population.

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The answer of From a population of 2000 accounts receivable,a...

Question 4

The accounting firm of Nancy Ahmadi & Associates (NAA)was commissioned to audit a population of 500 accounts.For this audit,NAA selected a simple random sample of 64 accounts.The sample showed an average discrepancy of $120 with a standard deviation of $24.
a.Estimate the population total discrepancy.
b.Develop an approximate 95% confidence interval for the population total discrepancy.

Accepted Answer

The answer of The accounting firm of Nancy Ahmadi &...

Question 5

Assume simple random sampling has been used,and the following information was obtained.
  
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean.

Accepted Answer

The answer of Assume simple random sampling has been used,and...

Question 6

A university has 5,000 students.The manager of food services at the university is interested in determining the total lunch expenditure.A simple random sample of 121 lunch receipts was selected.The sample showed an average of $3 with a standard deviation of $0.40.
a.Estimate the standard error of the sample mean.
b.Develop an approximate 95% confidence interval for the population mean.
c.Estimate the population's total expenditure for lunch.
d.Develop an approximate 95% confidence interval for the total expenditure for lunch.

Accepted Answer

The answer of A university has 5,000 students.The manager of...

Question 7

Nancy Joon,Inc.has 1500 employees.A simple random sample of 81 employees was selected,and the individuals in the sample were asked how much they contribute (monthly)to their retirement accounts.The sample mean,  
,was $150 with a standard deviation,s,of $45. 
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean.

Accepted Answer

The answer of Nancy Joon,Inc.has 1500 employees.A simple random sample...

Question 8

Exhibit 22-4
Simple random sampling has been used to obtain a sample of size 50 from a population of size 500.The sample proportion was 0.7.
-Refer to Exhibit 22-4.An approximate 95% confidence interval for the population proportion is
A)0.500 to 0.700
B)0.750 to 0.810
C)0.576 to 0.824
D)0.638 to 0.762

Accepted Answer

The approximate 95% confidence interval for the population proportion can be calculated using the formula: sample proportion +/- (Z-score for 95% confidence level) * standard error, where the standard error is the square root of [(sample proportion * (1 - sample proportion)) / sample size]. Plugging in the given values, we get: 
0.7 +/- (1.96) * sqrt[(0.7 * 0.3) / 50] 
= 0.7 +/- 0.113 
= (0.587, 0.813)
So, the best choice is C) 0.576 to 0.824 which is the closest to the calculated interval.

Question 9

A stratified simple random sample has been taken with the following results.
  
a.Determine a point estimate for the mean of the population.
b.Estimate the standard error of the mean.
c.Approximate a 95% confidence interval for the population mean.
d.Compute the population total.
e.Determine a 95% confidence interval for the population total.

Accepted Answer

The answer of A stratified simple random sample has been...

Question 10

A simple random sample of size 36 is selected from a population of size 750.The sample mean is 318,and the sample standard deviation is found to be 30.
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean.

Accepted Answer

The answer of A simple random sample of size 36...

Question 11

The following are the results provided by a stratified simple random sample.
  
a.Determine a point estimate for the mean of the population.
b.Estimate the standard error of the mean.
c.Approximate a 95% confidence interval for the population mean.
d.Compute the population total.
e.Determine a 95% confidence interval for the population total.

Accepted Answer

The answer of The following are the results provided by...

Question 12

Simple random sampling has been used to obtain a sample of 81 elements from a population of size 500.The sample mean is 120,and the sample standard deviation is determined to be 36.
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean.
c.Estimate the population total.
d.Develop an approximate 95% confidence interval for the population total.

Accepted Answer

The answer of Simple random sampling has been used to...

Question 13

The following are the results of a stratified random sample.
  
a.Determine the point estimator of the population proportion.
b.Estimate the standard error of the population proportion.
c.Develop an approximate 95% confidence interval for the population proportion.

Accepted Answer

The answer of The following are the results of a...

Question 14

From a population consisting of 8,000 elements,a sample of size 121 is selected.The sample has a mean of 4,000 and a standard deviation of 600.
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean.
c.Estimate the population total.
d.Develop an approximate 95% confidence interval for the population total.

Accepted Answer

The answer of From a population consisting of 8,000 elements,a...

Question 15

A community has 2,000 registered voters.A pilot study revealed that 70% of the individuals are planning to vote for the incumbent mayor.We are interested in selecting a sample.So that the sampling error will not exceed 4%,what size sample should be taken?

Accepted Answer

The answer of A community has 2,000 registered voters.A pilot...

Question 16

Simple random sampling has been used to obtain a sample of n = 40 elements from a population of N=300.The sample proportion  
a.Estimate the standard error of the proportion.
b.Develop an approximate 95% confidence interval for the population proportion.

Accepted Answer

The answer of Simple random sampling has been used to...

Question 17

A stratified simple random sample has been taken with the following results.
  
a.Determine the point estimator of the population proportion.
b.Estimate the standard error of the population proportion.
c.Develop an approximate 95% confidence interval for the population proportion.

Accepted Answer

The answer of A stratified simple random sample has been...

Question 18

Simple random sampling has been used to obtain a sample of size 60 from a population of size 700.The sample mean was 500 with a standard deviation of 60.
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean.

Accepted Answer

The answer of Simple random sampling has been used to...

Question 19

A random sample of 60 elements was selected from a population of size 400.The sample proportion  
a.Estimate the standard error of the proportion.
b.Develop an approximate 95% confidence interval for the population proportion.

Accepted Answer

The answer of A random sample of 60 elements was...

Question 20

A company has 600 employees.A random sample of 49 employees took a computer literacy test.The sample resulted in a mean score of 75 with a standard deviation of 21.
a.Estimate the standard error of the mean.
b.Develop an approximate 95% confidence interval for the population mean of the 600 employees.

Accepted Answer

The answer of A company has 600 employees.A random sample...

Quiz 22: Sample Survey

Assume simple random sampling has been used,and the following information was obtained. a.Estimate the standard error of the mean. b.Develop an approximate 95% confidence interval for the population mean.

Exhibit 22-4 Simple random sampling has been used to obtain a sample of size 50 from a population of size 500.The sample proportion was 0.7. -Refer to Exhibit 22-4.An approximate 95% confidence interval for the population proportion is

A simple random sample of size 36 is selected from a population of size 750.The sample mean is 318,and the sample standard deviation is found to be 30. a.Estimate the standard error of the mean. b.Develop an approximate 95% confidence interval for the population mean.

The following are the results of a stratified random sample. a.Determine the point estimator of the population proportion. b.Estimate the standard error of the population proportion. c.Develop an approximate 95% confidence interval for the population proportion.

A community has 2,000 registered voters.A pilot study revealed that 70% of the individuals are planning to vote for the incumbent mayor.We are interested in selecting a sample.So that the sampling error will not exceed 4%,what size sample should be taken?

Simple random sampling has been used to obtain a sample of n = 40 elements from a population of N=300.The sample proportion a.Estimate the standard error of the proportion. b.Develop an approximate 95% confidence interval for the population proportion.

A stratified simple random sample has been taken with the following results. a.Determine the point estimator of the population proportion. b.Estimate the standard error of the population proportion. c.Develop an approximate 95% confidence interval for the population proportion.

Simple random sampling has been used to obtain a sample of size 60 from a population of size 700.The sample mean was 500 with a standard deviation of 60. a.Estimate the standard error of the mean. b.Develop an approximate 95% confidence interval for the population mean.

A random sample of 60 elements was selected from a population of size 400.The sample proportion a.Estimate the standard error of the proportion. b.Develop an approximate 95% confidence interval for the population proportion.