Example 3: using a spreadsheet to find normal probabilities
return to the information given in example 1. the usda, in its official food plans (), states that the average cost of food for a 14- to 18-year-old male
(on the moderate-cost plan) is $261.50 per month. assume that the monthly food cost for a 14- to 18-year-old male is approximately normally distributed with a mean of $261.50 and a
standard deviation of $16.25. round your answers to four decimal places.
use a spreadsheet to find the probability that the monthly food cost for a randomly selected 14- to 18-year-old male is
a. less than $280.
b. more than $270.
c. more than $250.
d. between $240 and $275.