A bag contains 4 red marbles, 4 black marbles, 4 orange marbles, 3 blue marbles, 2 pink marbles, and 5 green marbles. If 2 marbles are selected, what is the probability of picking 2 blue marbles?

There are LaTeX: \displaystyle C(22,2)=231 to select 2 marbles. There are LaTeX: \displaystyle 3 ways to select 2 blue from 3 blue. This gives the probability LaTeX: \displaystyle \frac{1}{77}