##### Practice Final, B5
jferrermartinez
Hey guys! I tried solving this problem by making a tree and got P(you and your friend on the same team | you are on math team) = 3/19. Did anybody get something different?
martha2A: March 18, 2015, 9:44 p.m.
I got the same answer as you :)
rahulchandrupatla: March 19, 2015, 1:57 p.m.
I did the problem the way the professor went over in the review session, which comes out to $\frac{(18choose2)}{(19choose3)}$ and when i plug it into a calculator that's the same as 3/19, so your answer should be correct!
Lilyhui: March 19, 2015, 5:26 p.m.