Budi has 2 pairs of black shoes and 3 pairs of brown shoes. He also has 3 pairs of red socks, 4 pairs of brown socks, 6 pairs of black socks. If you choose a pair of shoes and a pair of socks at random, find the probability that the colors you choose are black and brown (black shoes and brown socks, or brown shoes and black socks).

The answer is 2/5, please explain why?