# Math Help - Permutations and Combinations

1. ## Permutations and Combinations

I have this question:
How many subsets with 7 elements does a set with 9 elements have?
Can someone show me how to solve this or a similar problem?

2. Originally Posted by malfist
Can someone show me how to solve this or a similar problem?
This is a simple combination: ${9 \choose 7} = \frac{9!}{(7!)(2!)}$