Question

Evaluate $\frac{n!}{(n-r)!}$, when n=9, r=5.

Answer 1

I hope answer is correct

Answer 2

Answer:

15,210

Step-by-step explanation:

we know that factorial of any natural number can be calculated as

n! = n . n-1. n-2...n-(n-1)

So

here to calculate $\frac{n!}{(n-r)!}$

where n=9,r=5

$\frac{9!}{(9-5)!}\\\\\\=\frac{9.8.7.6.5.4.3.2.1}{4.3.2.1} \\\\\\=9.8.7.6.5\\\\\\=72(7)(30)\\\\=504(30)\\\\=15,120$