Probability of both being Red

Question

Suppose a jar contains 16 red marbles and 33 blue marbles. If you reach in the jar and pull out 2 marbles at random at the same time, find the probability that both are red.

Answer 1

There is no difference whether you reach in one at a time and pull the two marbles or if you grab two at once. The probability the one will be red is 16/49 and the probability the other is red is then 15/48. The probability both will be red is 16/49 * 15/48 = 240/2352 = 5/49