A girl has 3 shirts (red, yellow, blue) and 6 pairs of socks (red, blue, green, orange, white, black). What is the probability her socks and shirt will both be yellow or both be blue?

Question

The answers are:

A. 1/18

B. 1/9

C. 1/6

D. 1/8

Answer 1

Chance that shirt is blue = 1/3

Chance that socks are blue = 1/6

Chance that both are blue = 1/3 x 1/6 = 1/18 (A)

Could also create a tree diagram to visualize the result. There are 18 possible outcomes (combinations), only one of which is blue & blue.

Answer 2

Peter R.

Your analysis is correct, but the question asked for the probability that both would be blue OR both would be yellow. Therefore, since there is only one way to get both blue and only one way to get both yellow, the probability is 2/18=1/9.