1. The problem statement, all variables and given/known data Ok, my teacher wants us to compute: (2n choose n)^2/(4n choose 2n) using Stirling's formula. 2. Relevant equations Stirling's formula is sqrt(2pi) e^-n * n^(n+.5) 3. The attempt at a solution Ok, I'm just confused about how you compute something with n in it....I mean, I get how to use Stirling's formula for factorials, but how do you compute that probability that is requested when there are ns in the (2n choose n)^2/(4n choose 2n)....what do I plug into stirling's formula? I don't know how to really attempt a sensible solution when I don't know what to put for n. Thanks.