A bag contains 5 green balls and 8 white balls. If two balls are drawn simultaneously, what is the probability that both balls are the same colour?
Pick: A) 3/7 B) 6/11 C) 12/21 D) 19/39 E) 29/49
The total number of ways to draw two balls is 13C2 = 78   The number of ways to draw two green balls is 5C2 = 10   The number of ways to draw two white balls is 8C2 = 28   P(two balls of the same colour) = 38/78 = 19/39   The answer is 19/39.
<result>D</result>
A bag contains 5 green balls and 8 white balls. If two balls are drawn simultaneously, what is the probability that both balls are the same colour?