Question

Suppose you have a drawer full of white, black, and yellow pairs of socks. If the probability of picking a white pair of socks is 4/9, and the probability of picking a black pair of socks is 7/18, what is the probability of picking a yellow pair of socks?

a. 1/6
b 5/25
c 7/15 d 16/27

Answer 1

A. 1/6

If you turn 4/9 into 8/18 that would make it easier to figure out because you would have the same denominator.
So then you can add 8/18 and 7/18 to get 15/18 so you know that whats left (3/18) id the probobility of yellow socks. If you simplify 3/18 you get 1/6.