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# I need help!

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This is my first time doing this can someone explain hoe to do permutations?

Compute $\binom{223}{221}$.

Guest Jun 10, 2018
#1
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Permutation: A set of objects in which position (or order) is
important. Example: nPr=68P5=68! / [68 - 5]! = 1,250,895,360

Combination: A set of objects in which position (or order) is NOT
important. Example: nCr=68C5= 68! / [(68 - 5)! . 5!] = 10,424,128

Guest Jun 10, 2018
#2
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Permutations: n!/(n-r)!=$$\frac{223!}{(223-221)!}=\frac{223!}{2!}=3*4*...........*223$$

tertre  Jun 10, 2018