A publisher wants to estimate the mean length of time (in minutes) all adults spend reading newspapers. To determine this estimate, the publisher takes a random sample of 15 people and obtains the results below. From past studies, the publisher assumes is 2.1 minutes and that the population of times is normally distributed.

66 1010 1212 66 66 1010 77 77 88 88 1111

Construct the 90% and 99% confidence intervals for the population mean. Which interval is wider? If convenient, use technology to construct the confidence intervals.

The 90% confidence interval is ( ___ , ____). (Round to one decimal place as needed.)