A box contains 9 pairs of shoes (18 shoes in total). If two shoes are selected at random, what it is the probability that they are matching shoes?
Pick.
A) 1/190  B) 1/17  C) 1/19  D) 1/10  E) 1/9
The problem with your solution is that we don't choose 1 shoe from 18, but rather choose the needed one AFTER we just took one and need the second to be the pair of it. So, the probability would simply be: 1/1*1/17(as after taking one at random there are 17 shoes left and only one is the pair of the first one)=1/17   Answer: 1/17.
<result>B</result>
A box contains 9 pairs of shoes (18 shoes in total). If two shoes are selected at random, what it is the probability that they are matching shoes?