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.

Question

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.

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The Answer of 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.