Question

Evaluate the expression: 15c4
A. 8,190
B. 32,760
C. 1,365
D. 5,460

Answer 1

1365

Explanation:

15!/4!(15-4)!

1365

Answer 2

C. 1365

Explanation:

The expression nCr can be written with the simple equation:

n! / ((n-r)! * r!)

So to evaluate 15C4:

15! / ((15-4)! * 4!)

= 1365

So 15C4 = 1365

Cheers.