A bag contains 7 green balls and 7 white balls. If two balls are drawn simultaneously, what is the probability that both balls are the same colour? Pick one.
A) 4/13	B) 6/13	C) 8/21	D) 11/21	E) 17/42
The total number of ways to draw two balls is 14C2 = 91   The number of ways to draw two green balls is 7C2 = 21   The number of ways to draw two white balls is 7C2 = 21   P(two balls of the same colour) = 42/91 = 6/13   The answer is 6/13.
<result>B</result>
A bag contains 7 green balls and 7 white balls. If two balls are drawn simultaneously, what is the probability that both balls are the same colour?