I write "(1)" because I know I'll be creating more of these math help threads xD. This is about the combination formula. I understand the VERY BASICS of if, but if what I want to do 35 choose 20, or 20 choose 16 on a scientific calculator? For 20 choose 16, the answer will be one of the following: 4, 20, 36, 320, 480. But I'm just not sure. Can someone help explain it a little better?