A box contains 3 blue marbles, 4 red, 6 green marbles and 2 yellow marbles. If three marbles are picked at random, what is the probability that they are all blue?
Q1. A box contains 3 blue marbles, 4 red, 6 green marbles and 2 yellow marbles. If three marbles are picked at random, what is the probability that they are all blue?
Answer: 1/455
Explanation: All 3 blue marbles from 3 available out of 15 total: C(3,3)/C(15,3) = 1/455.