Chapter 9.6, Problem 46E

A large department of the Federal Government wants to determine whether the average number of business emails sent and received per business day by its employees differs from the average number of emails sent and received per day by corporate employees. Suppose the department electronically collects information on the number of business emails sent and received on a randomly selected business day over the past year from each of 10,163 randomly selected federal employees. The results are provided in the DATAfile named FedEmail. Assuming that the standard deviation of the number of emails sent and received by this department’s employees is σ = 25 and the average number of emails sent and received per day by corporate employees is 101.5, test the department’s hypothesis at α = .01. Discuss the practical significance of the results.