Sleeping outlier: A simple random sample of nine college freshmen were asked how many hours of sleep they typically got per night. The results were 8.5 24 9 8.5 8 6.5 6 7.5 9.5

Notice that one joker said that he sleeps 24 a day.

(a) The data contain an outlier that is clearly a mistake. Eliminate the outlier, then construct a 99.9% confidence interval for the mean amount of sleep from the remaining values. Round the answers to at least two decimal places.

(b) Leave the outlier in and construct the 99.9% confidence interval. Round the answers to at least two decimal places.