say 8/64 are red
then probability of two red is
8/64 * 7/63 = 1/8 * 7/63
the next one is yellow, again same answer
but now twice the probability
so in the end
8 * 1/8 * 7/63
= 7/63
A drawer contains 64 balls. Each ball is one of 8 colors, and there are 8 balls of each color. If the balls in the drawer are thoroughly mixed and you randomly choose two of them, what is the possibility that these two balls will have the same color?
1 answer