SOLUTION: Ms. Hariel's class has 21 students, how many combinations of 4 students can be made from the class?

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Question 486201: Ms. Hariel's class has 21 students, how many combinations of 4 students can be made from the class?
Answer by chessace(471) About Me  (Show Source):
You can put this solution on YOUR website!
Combos = Total! / (Subset! * (LeftOver!))
C = 21! / (4! * 17!)
C = (21*20*19*18*(17!) / ((4*3*2*1) * 17!)
C = (7*3 * 5*4 * 19 * 9*2) / (3*4*1*2)
C = 7*5*19*9 = 5985.