A university administrator wanted to estimate the average number of times students at her university drank alcohol in the past month. A random sample of 30 students was surveyed by phone. The average number of times students in the sample drank was 5.6 times. Assume that the population standard deviation is 6 times. Calculate a 95% confidence interval for the average number of times all students at the university drank alcohol in the past month.

Point estimate?

Margin of error?

Confidence Interval estimate?

How large of a sample is needed in order to cut the margin of error in half?