A simple random sample of 70 items resulted in a sample mean of 80. The population standard deviation is

A simple random sample of 40 items resulted in a sample mean of 30. The population...

A simple random sample of 40 items resulted in a sample mean of 30. The population standard deviation is σ = 20. a. Compute the 95% confidence interval for the population mean. Round your answers to one decimal place. Assume that the same sample mean was obtained from a sample of 100 items. Provide a 95% confidence interval for the population mean. Round your answers to two decimal places. What is the effect of a larger sample size on the...

{Exercise 8.3 (Algorithmic)} A simple random sample of 40 items resulted in a sample mean of...

{Exercise 8.3 (Algorithmic)} A simple random sample of 40 items resulted in a sample mean of 30. The population standard deviation is σ = 15. a. Compute the 95% confidence interval for the population mean. Round your answers to one decimal place. Enter your answer using parentheses and a comma, in the form (n1,n2). Do not use commas in your numerical answer (i.e. use 1200 instead of 1,200, etc.) b. Assume that the same sample mean was obtained from a...

A simple random sample of 70 items from a population with σ = 8 resulted in...

A simple random sample of 70 items from a population with σ = 8 resulted in a sample mean of 31. If required, round your answers to two decimal places. a. Provide a 90% confidence interval for the population mean. to b. Provide a 95% confidence interval for the population mean. to c. Provide a 99% confidence interval for the population mean.

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...

A simple random sample of 60 items resulted in a sample mean of 81. The population...

A simple random sample of 60 items resulted in a sample mean of 81. The population standard deviation is 17. 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 10 items resulted in a sample mean of 20. The population...

A simple random sample of 10 items resulted in a sample mean of 20. The population standard deviation is σ = 6. Round your answers to two decimal places. a. What is the standard error of the mean, σx? b. At 95% confidence, what is the margin of error?

A simple random sample of 70 items from a population with = 8 resulted in a...

A simple random sample of 70 items from a population with = 8 resulted in a sample mean of 34. If required, round your answers to two decimal places. a. Provide a 90% confidence interval for the population mean. to b. Provide a 95% confidence interval for the population mean. to c. Provide a 99% confidence interval for the population mean.