A bag contains 10 green marbles and 4 yellow marbles. If two marbles are chosen at random, one at a time and without replacement, what is the probability of getting two green marbles?

P(green), is 10/14=5/7 because there are 10 green marbles out of the total 14.
P(2nd green), is 9/13 because there are only 9 green marbles and only 13 total marbles. Then you multiply them 5/7 x 9/13 = 35/117