Grouped Data: Shoplifting What is the age distribution of adult shoplifters (21 years of age or older) in supermarkets? The following is based on information taken from the National Retail Federation.

A random sample of 895 incidents of shoplifting gave the following age distribution:

Age range

(years)

21–30 31–40 41 and over Number of shoplifters 260 348 287.

Estimate the mean age, sample variance, and sample standard deviation for the shoplifters. For the class 41 and over, use 45.5 as the class midpoint.AppendixLO1