For Exercises 39–46, let the random variable be normally distributed, with mean and standard deviation . Suppose we take random samples of size . For Exercises 41–46, find the indicated values of :
45. The two symmetric values for the sample mean that contain the middle 90% of sample means. (Hint: Use your answers to Exercises 41 and 42.)
7.1.45
8.35 and 11.65