1. The problem statement, all variables and given/known data A class consists of 50 students, 30 of which are Math majors. Five students are selected at random to form an advisory committee. How many possible committees contain at least 3 Math majors? 2. Relevant equations n choose r = n!/((n-r)!r!) and we say that represents the number of possible combinations of n objects taken r at a time. 3. The attempt at a solution Maybe I'm going about this the wrong way, but since we need at least 3 math majors that means we can have 3, 4, or 5 math majors in the committee. The way to have exactly 3 is (30 choose 3)*(20 choose 2). The way to have exactly 4 is (30 choose 4)*(20 choose 1), and the way to have exactly 5 is (30 choose 5)*(20 choose 0). So the number of possible committees that contain at least 3 math majors would be the sum of all of these possibilities, which equals 1,462,006.