Calculating n!(N-n)!: N = 16, n = 3

Thread starter mouse
Start date Mar 13, 2005

Mar 13, 2005

mouse

N!
____
n!(N - n)!

N = 16 n = 3

so,

16!
____
3!13! = 560

i don't know how to get the 560 answer?

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Mar 13, 2005

gnome

(16*15*14)/(3*2*1)

Mar 13, 2005

chroot

Staff Emeritus

Science Advisor

Gold Member

You can write a factorial like 16! as 16*15*14*13!.

The 13! then cancels on top and bottom, leaving what gnome indicated.

- Warren

Mar 14, 2005

mouse

thanks

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