JWU Statistics Worksheet


You are given the sample mean and the population standard deviation. Use this information to construct the 90% and 95% confidence intervals for the population mean. Interpret the results and compare the widths of the confidence intervals.

From a random sample of 32 business days, the mean closing price of a certain stock was $114.13 Assume the population standard deviation is $10.99

The 90% confidence interval is (nothing,nothing).