# Math Help - not a permutation? then how?

1. ## not a permutation? then how?

There are two small towns, Greenville and Yellowville. Greenville contains 20 houses and Yellowville contains 15 houses. The state safety inspector is asked to randomly inspect 5 houses in Greenville and 7 houses in Yellowville. In how many ways can this be done (Hint: this is not a permutation)?

2. Hello,

This is a combination.

You "take" 5 elements among 20 elements (the houses).

Combination - Wikipedia, the free encyclopedia

3. thank you. I think I am making it more difficult than it really is.

4. Originally Posted by dreamer1963
There are two small towns, Greenville and Yellowville. Greenville contains 20 houses and Yellowville contains 15 houses. The state safety inspector is asked to randomly inspect 5 houses in Greenville and 7 houses in Yellowville. In how many ways can this be done (Hint: this is not a permutation)?
${20 \choose 5} \times {15 \choose 7}$