For an insurance company, the ability to deliver approved policies to customers in a timely
manner is critical. Last year, the mean processing time was 45 days. To determine if the mean
processing time has been changed from last year, a random sample of 27 approved policies is selected
and the total processing time (in days) is recorded:
73 19 16 64 28 28 31 90 60 56 31 56 22 18 45 48 17 17 17 91 92 63 50 51 69 16
At the 0.05 level of confidence, is there evidence that the mean processing time has changed from 45
days?