Question

A pencil bag contains 24 red pencils, 15 blue pencils, and 8 green pencils. Without looking, Carrie selects a pencil, gives it to her friend, and then selects another pencil.

What is the probability that Carrie selected a blue pencil for her friend and a red pencil for herself?

Write your answer as a percent. Round to the nearest tenth of a percent.

Answer 1

First, add up all the pencils in the bag: 24 + 15 + 8 = 47 pencils in total.
Next, put the probability into a fraction: The probability of selecting a red pencil is 24/47 and the probability of selecting a blue pencil after is 15/46. 24/47 x 15/46 = 360/2162. 
Next, change the fraction into a percent: 360/2162 = 0.166512488 which is 16.6512488%. Round it to the nearest tenth of a percent and you get 16.7%.