Michael has 4 red shirts, 3 green shirts, and 5 blue shirts in his closet. If he randomly selects a shirt what is the probability that he chooses blue or red?

1 Answer
Nov 15, 2016

#P(B " or " R) = 3/4#

Explanation:

Michael has 12 shirts altogether.

The probability that he chooses either blue or red means there are 9 shirts which are possible.

#"Probability" = "number of desirable outcomes"/"total number of possible outcomes"#

#P(B " or " R) = 9/12 = 3/4#

Note that the probability of blue or red is the same as the shirt NOT being green. He has 3 green shirts.

#P("Not Green") = 1- P(G)#

=#1-3/12 = 9/12 = 3/4#