Question

What is the value of the expression?

10!/5!2!

720

1

30,240

15,120

Answer 1

Setup:

`(10!)/(5!*2!) = (10*9*8*7*6*5*4*3*2*1)/(5*4*3*2*1*2*1)`

Cancel out numbers from top and bottom to get

`5*9*8*7*6 = 15120`

Answer 2

10! = 10 * 9 * 8* 7 *6 *5 *4 *3 *2 *1 = 3628800

5! = 5*4*3*2*1 = 120
2! = 2*1 = 2

5! x 2! = 120 * 2 = 240

10! / 5!2! = 362880 / 240 = 15,120