Combination and permutation??

Mathematics for Computing
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AndyCharles
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Combination and permutation??

Post by AndyCharles » Thu Sep 15, 2011 3:31 pm

Can someone explain to me the key difference as to why the Combination and permutation formulas are different by n!

Combination=
C(n,r)=n!/(n-r)!

Permutation=
P(n,r)=n!/n!(n-r)!

Any help would be very beneficial for me.

Thanks and Regards
Andy Charles
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Saman
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Re: Combination and permutation??

Post by Saman » Thu Sep 15, 2011 6:03 pm

If you have searched the forum, you would have found the following articles.

What is Permutations & Combinations?

Another topic on this subject. Need help on Permutations.
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