Question

A box contains 3 yellow, 2 red, 4 green and 3 black marbles. Two marbles are taken one after the other at random from the box. What is the probability that both marbles are red?

a) 1/50
b) 1/60
c) 1/66
d) 2/57
e) 1/6

Answer 1

2/12 times 1/11 equals 1/66

Answer 2

It should be C. There are 12 marbles total, and 2 of them are red, so 2/12 or 1/6.
After the first one is drawn there are 11 marbles left 1 of which is red, so 1/11
1/11•1/6=1/66