4 professors and 6 students are being considered for membership on a supervisory committee which must consist of 3 people. If the committee has to include at least 3 professor, how many ways can this committee be formed?	Choose the correct choice
A) 36	B) 60	C) 72	D) 80	E) 100
you count up combinations twice.   4*9*8... and let me name 6 with students A,B,C,..,F   after choosing a professor, when you choose Student A and B, you can choose A first, then B. Or B first, then A. Both combination are same.   I don't think that's the only mistake.   36 is a factor of = 2^2*3^2   72 is a factor of = 2^3*3^2.   These are very different numbers and you cannot divide 72 with something to get to 36. ans 36
<result>A</result>
4 professors and 6 students are being considered for membership on a supervisory committee which must consist of 3 people. If the committee has to include at least 3 professor, how many ways can this committee be formed?