Waist size: According to the National Health Statistics Reports, a sample of 783 men aged 20– 29 years had a mean waist size of 36.9 inches with a standard deviation of 8.8 inches.
a. Construct a 95% confidence interval for the mean waist size.
b. The results of another study suggest that the mean waist size for men aged 30– 39 is 38.7 inches. Based on the confidence interval, is it reasonable to believe that the mean waist size for men aged 20– 29 may be 38.7 inches? Explain.