A box contains 5 yellow balls, 3 blue, and 1 red ball. Two balls are drawn at random. Find the probability that:

Question

The two balls have the same color

Answer 1

you could pick either two yellow or 2 blue
prob(your event) = (5/9)(4/8) + (3/9)(2/8)
= 5/18 + 1/12
= 13/36

or ( C(5,2) + C(3,2) )/C(9,2)
= same as above