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

C(n,3) = C(n,8)

2. Relevant equations

n!/(n-3)!3! = n!/(n-8)!8!

3. The attempt at a solution

My attempts at a solution are many and varied. But, I figure my problem is with the algebraic operations on factorials. Logically, since the numerators are both n!, I figure that I can ignore that and just work on (n-3)!3! = (n-8)!8!

I boiled this down to (n-3)!/(n-8)! = 6720. I solved this based on the fact that I know that 8!/3! = 6720. Therefore, (n-3)! = 8!, and n = 11. But this was simply guess work on my part. What I'm confused about is, what is the proper way to solve the problem? How do I perform algebra on these factorials?

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# Homework Help: Combination Problem

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