posted by Mary on .
A box contains 4 red cubes, 3 blue cubes, 2 green cubes, and 1 yellow cube. You pick two cubes at random, replacing each after you pick. Find the probability of each compound event.
RR RB RG RY
BB BG BY
(The order does not matter)
I will do one of them, you do the rest
Prob(B or G) = C(3,1)*C(2,1)/C(10,2) = 6/45 = 2/15
Prob(BG) = (3/10)(2/9) = 6/90
prob (GB) = (2/10)(3/9) = 6/90
prob (B or G) = 6/90 + 6/90 = 6/45