Question

A random sample of 100 credit sales in a department store showed a sample mean of...

A random sample of 100 credit sales in a department store showed a sample mean of $64. The population standard deviation is known to be $16.

A) Provide a 99% confidence interval for the population mean.

B) Provide a 95% confidence interval for the population mean.

C) Describe the effect of a lower confidence level on the margin of error.

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
In examining the credit accounts of a department store, an auditor would like to estimate the...
In examining the credit accounts of a department store, an auditor would like to estimate the true mean account error (book value – audited value). To do so, the auditor selected a random sample of 50 accounts and found the mean account error to be $60 with a standard deviation of $30. a. Construct a 95% confidence interval for the population mean account error. What conclusion can be made from this confidence interval? b. How large a sample is actually...
A statistics practitioner took a random sample of 80 observations from a population with a standard...
A statistics practitioner took a random sample of 80 observations from a population with a standard deviation of 25 and compute the sample mean to be 100. (a) Estimate the population mean confidence interval with 90% confidence level, 95% confidence level and 99% confidence level. (b) Describe the effect of increasing the confidence level on the confidence interval. (c) At 99% confidence level, if the population standard deviation is reduced to 16, will the confidence interval be wider or narrower?
A simple random sample with n = 52 provided a sample mean of 28.5 and a...
A simple random sample with n = 52 provided a sample mean of 28.5 and a sample standard deviation of 4.4. (Round your answers to one decimal place.) (a) Develop a 90% confidence interval for the population mean. to (b) Develop a 95% confidence interval for the population mean. to (c) Develop a 99% confidence interval for the population mean. to (d) What happens to the margin of error and the confidence interval as the confidence level is increased? As...
A simple random sample with n=50provided a sample mean of 23.5 and a sample standard deviation...
A simple random sample with n=50provided a sample mean of 23.5 and a sample standard deviation of 4.3 a. Develop a 90% confidence interval for the population mean (to 1 decimal).   ,   b. Develop a 95% confidence interval for the population mean (to 1 decimal).   ,   c. Develop a 99% confidence interval for the population mean (to 1 decimal).   ,   d. What happens to the margin of error and the confidence interval as the confidence level is increased?
A simple random sample with n=56 provided a sample mean of 23.5 and a sample standard...
A simple random sample with n=56 provided a sample mean of 23.5 and a sample standard deviation of 4.5. a. Develop a 90% confidence interval for the population mean (to 1 decimal). (_____, ______) b. Develop a 95% confidence interval for the population mean (to 1 decimal). (_____, ______) c. Develop a 99% confidence interval for the population mean (to 1 decimal). (_____, ______) d. What happens to the margin of error and the confidence interval as the confidence level...
A simple random sample with N=52 provided a sample mean of 21.0 and a sample standard...
A simple random sample with N=52 provided a sample mean of 21.0 and a sample standard deviation of 4.4. a. Develop a 90% confidence interval for the population mean (to 1 decimal). (________, _________) b. Develop a 95% confidence interval for the population mean (to 1 decimal). (________, _________) c. Develop a 99% confidence interval for the population mean (to 1 decimal). (________, _________) d. What happens to the margin of error and the confidence interval as the confidence level...
A simple random sample of 60 items resulted in a sample mean of 91. The population...
A simple random sample of 60 items resulted in a sample mean of 91. The population standard deviation is 12. a. Compute the 95% confidence interval for the population mean (to 1 decimal). ( , ) b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean (to 2 decimals). ( , ) c. What is the effect of a larger sample size on the margin of...
A simple random sample of 60 items resulted in a sample mean of 79. The population...
A simple random sample of 60 items resulted in a sample mean of 79. The population standard deviation is 13. a. Compute the 95% confidence interval for the population mean (to 1 decimal). b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean (to 2 decimals). c. What is the effect of a larger sample size on the margin of error?
A simple random sample of 60 items resulted in a sample mean of 71. The population...
A simple random sample of 60 items resulted in a sample mean of 71. The population standard deviation is 14. a. Compute the 95% confidence interval for the population mean (to 1 decimal). b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean (to 2 decimals). c. What is the effect of a larger sample size on the margin of error?
A simple random sample of 60 items resulted in a sample mean of 71. The population...
A simple random sample of 60 items resulted in a sample mean of 71. The population standard deviation is 13. a. Compute the 95% confidence interval for the population mean (to 1 decimal). ( , ) b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean (to 2 decimals). ( , ) c. What is the effect of a larger sample size on the margin of...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT