In a recent year, the Federal Communications Commission reported that the mean wait for repairs for AT&T customers was 25.3 hours. In an effort to improve this service, suppose that a new repair service process was developed. This new process, used for a sample of 100 repairs, resulted in a sample mean of 22.3 hours and a sample standard deviation of 8.3 hours.
a. Is there evidence that the population mean amount is less than 25.3 hours? (Use a 0.05 level of significance.)
b. Determine the p-value and interpret its meaning.