mathdad
Full Member
- Joined
- Apr 24, 2015
- Messages
- 925
Find the number of combinations of 4 different color pencils taken 2 at a time.
I was told by a friend to use the following formula:
nCr = n! /[r! (n - r)!], where n is 4 and r is 2.
Let me see if I can do this.
4C2 = 4!/[2!(4 - 2)!]
4C2 = 24/[2(2)!]
4C2 = 24/[2(2)]
4C2 = 24/4
4C2 = 6
There are 6 combinations.
You say?
I was told by a friend to use the following formula:
nCr = n! /[r! (n - r)!], where n is 4 and r is 2.
Let me see if I can do this.
4C2 = 4!/[2!(4 - 2)!]
4C2 = 24/[2(2)!]
4C2 = 24/[2(2)]
4C2 = 24/4
4C2 = 6
There are 6 combinations.
You say?