+0

+1
117
2
+69

Jimmy is going on a quick vacation, and is packing some clothes. He has twelve shirts, and wants to take three of them with him. How many ways can Jimmy choose his shirts?

rohitaop  May 18, 2018
#1
+87604
+2

He  can choose any 3 of the 12 shirts  =

C (12,3)   = 220 different choices

CPhill  May 18, 2018
#2
+2766
+1

This is combinations because he can choose any 3 shirts from the 12 total.

We use the formula, $$\frac{n!}{r!*(n-r)!}$$

Plugging the values in, we have: $$\frac{12!}{3!*(9!)}=\frac{12*11*10}{3*2*1}=44*5=\boxed{220}$$ ways.

tertre  May 19, 2018