Question

The new director of a local unemployment service office believed that the average time of 28 minutes in line for an application was too long. Therefore, it introduces a series of changes to speed up the process. Three weeks later a sample of size 127 was selected. As each unemployed person entered the office to process an application, they were given a card that marked their arrival time. When the request was received, the time was re-recorded. The mean waiting time was calculated to be 26.9 minutes, and the sample standard deviation was 8 minutes. Should the null hypothesis of u = 28 be rejected in favor of the alternative hypothesis of <28 at the 0.02 significance level?

Answer 1