Best known for its testing program, ACT, inc. also compiles data on a variety of issues in
education. In 2004 the company reported that
the national college freshman-
to-sophomore retention rate held steady at 74% over the previous four years. Consider random samples of 400 freshmen who took the ACT.

1. What are the mean and standard deviation of
the sampling distribution of size n = 400?

2.Is this sampling distribution approximately
normal?

3. What is the probability that the freshman-to-
sophomore retention rate is lower than 7 out
of 102