(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

How many subsets S [tex]\subseteq[/tex] {1,2,...,21} are there if S is required to contain 5 odd integers and 6 even integers?

2. The attempt at a solution

I am having trouble breaking this one down. If the subsets contain 5 odd and 6 even, do they only contain 5 odd and 6 even? That would be 11 elements in the set. So the first element would have 11/21 chance of being odd, the second would have 10/20,... until 7/17 for the fifth. The sixth would have a 10/16 chance of being even, seventh a 9/15,...and the eleventh would have 5/11. Am I even going the right direction?

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# Homework Help: Basic Combinatorics Question

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