SOLUTION: Prove nCr = n/(n-r) * n-1Cr using an analytic and combinatoial proof

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Question 431819: Prove nCr = n/(n-r) * n-1Cr using an analytic and combinatoial proof
Answer by richard1234(7193)   (Show Source): You can put this solution on YOUR website!
The right hand side is equal to



Since , and the right hand side is equal to

, same as the left hand side.

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