Answer
12650
Work Step by Step
The number of possible combinations if r items are taken from n items is
nCr = $\frac{n!}{r!(n-r)!}$
25C4 = $\frac{25!}{4!(25 -4)!}$
=$\frac{25!}{4!21!}$
=$\frac{25*24*23*22*21!}{4!21!}$
=$\frac{25*24*23*22}{4*3*2*1} \\= 12650$
