Chapter 8, Problem 37P

Use the following information to answer the next 14 exercises: The mean age for all Foothill College students for a recent Fall term was 33.2. The population standard deviation has been pretty consistent at 15. Suppose that twenty-five Winter students were randomly selected. The mean age for the sample was 30.4. We are interested in the true mean age for Winter

Foothill College students. Let X = the age of a Winter Foothill College student.

Construct a 95% Confidence Interval for the true mean age of P.4nrer Foothill College swderns by working out then answering the next seven exercises.

Using the same mean, standard deviation, and sample size. how would the enor bound change if the confidence level were reduced to 90%? Why?