Question

A bag of numbered lottery balls contains the numbers 1 through 60. What is the probability that a randomly selected ball will be a number that is not between 15 and 23, inclusive?

Answer 1

15% is your answer.

Explanation:

Divide 1 by 60 and multiply that by the number of marbles that you want to find the probability of, so 9. 15, 16, 17, 18, 19, 20, 21, 22, 23.

Answer 2

17/20

Explanation:

There are 9 numbers between 15 and 23, inclusive. So the probability of getting a number in that range is 9/60. Therefore, by the complement rule, the probability of not getting one of these numbers is 17/20