The mean television viewing time for Americans is 15 hours per week (Money, November 2003). Suppose a sample of 60 Americans is taken to further investigate viewing habits.
Assume the population standard deviation for weekly viewing time is σ = 4 hours.
a. What is the probability the sample mean will be within 1 hour of the population mean?
b. What is the probability the sample mean will be within 45 minutes of the population mean?