# Question

A simple random sample of 60 items resulted in a sample mean of 80. The population standard deviation is σ = 15.

a. Compute the 95% confidence interval for the population mean.

b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean.

c. What is the effect of a larger sample size on the interval estimate?

a. Compute the 95% confidence interval for the population mean.

b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean.

c. What is the effect of a larger sample size on the interval estimate?

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