When to use the formula (nCr x nCr)/nCr?

AI Thread Summary
The discussion revolves around the formula (nCr x nCr)/nCr and its application in combinatorial problems. Participants clarify that the formula simplifies to nCr, highlighting the importance of distinguishing between different variables in combinatorial contexts. An example using specific values, such as 5C2 x 4C3, is mentioned to illustrate the formula's use. The conversation emphasizes the need for clarity in notation to effectively address combinatorial questions. Understanding the context and proper usage of the formula is crucial for solving related problems.
jasper10
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Homework Statement



I was wondering for what situations one uses the formula:
(nCr x nCr)/ nCr ?
Thanks

Homework Equations



nCr
 
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jasper10 said:
I was wondering for what situations one uses the formula:
(nCr x nCr)/ nCr ?
You mean (nCr x nCr)/ nCr = nCr? ;)

There's a reason you use different letters to represent different quantities. It's hard to answer your question when you have removed all that information from the formula.
 
well i mean for example,

5C2 x 4C3 / nCr
 

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