The mean number of hours of flying time for pilots at Air-Fly Airlines is 39 hours per month with a sample standard deviation of 8.5 hours. Assume that this mean was based on actual flying times for a random sample of its 28 pilots. Construct the 95% confidence interval for the mean number of hours of flying time for pilots at Air-Fly Airlines.
A closed competitor, United Fair Airlines, has a mean number of hours of flying time of 26 hours and a standard deviation of 13.2 hours per month. The mean was based on a randomly sampled 20 pilots from the airline. Construct the 95% confidence interval for the mean number of hours of flying time for pilots at United Fair Airlines.
ANS: 35.71 to 42.30 and 19.82 to 32.18
b) Is there any significant difference between the average flying times of the pilots for the two airlines? Assume that the mean number of hours of flying time is approximately normally distributed.
