Question

What is the age distribution of aduk shopifters (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 inddents of shoplifting gave the following age distribution. 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 (Round your answers to one decimal place.) Age range (years) 21-30 31.40 41 and over Number of shoplifters 271 343 21 x 2983 X 215213 X 5390 X

Answer 1

Age xifi Fix 2 21-30 31-40 141 and over Total midpoint Number of shoplifters If 25.5 271 35.5 343 45.5 281 895 6910.5 176217.8 112176.5 432265.8 12785.5 581740.3 31872.5 lig0224 E(X) = x= Efixi = 31872.5 [Fi Elx)= X = 35.1 895 E ( x² = I fix, Ifi E(+²) = 1329.859 1190224 895 s²= E(X²) E(X)]2 1329.859 - 35.1)? = 1329.859 1268 195 = 61.7 S = s? = 61.7 5- 7.9 X = 35.1 52= 61.7 s = 7.9