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.

After the seventh month of a 12-month loan: the numerator is: {(n + 11) + (n + 10) + (n + 9) + (n + 8) + (n + 7) + (n + 6) + (n + 5)} = , and the denominator is: {(n) + (n + 1) + + (n + 11)} = . therefore, the fraction is numerator/denominator (to the nearest tenth) = %

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab

Exclude leap years from the following calculations. (a) compute the probability that a randomly selected person does not have a birthday on october 4. (type an integer or a decimal rounded to three decimal places as needed.) (b) compute the probability that a randomly selected person does not have a birthday on the 1st day of a month. (type an integer or a decimal rounded to three decimal places as needed.) (c) compute the probability that a randomly selected person does not have a birthday on the 30th day of a month. (type an integer or a decimal rounded to three decimal places as needed.) (d) compute the probability that a randomly selected person was not born in january. (type an integer or a decimal rounded to three decimal places as needed.)