Permutation FormulaDate: 23 Apr 1995 06:27:14 -0400 From: Sam Grech Subject: Choose formula I can't for the life of me remember a particular formula. It's the formula for calculating the total possible number of ways to choose 'r' objects out of a total 'n' objects. I know it looks something like: p (n-r) ----- n+r2 - I know this is really far off but maybe you can tell from this which formula I mean.... By the way, it should not count repeated selections that are in a different order [ie: if you choose 2 objects out of a possible 'n' numbers, (1,2) and (2,1) would only count as one possibility]. Any help you could give would be appreciated. Sam Grech Date: 23 Apr 1995 11:33:47 -0400 From: Dr. Ken Subject: Re: Choose formula Hello there! Here's the formula you're looking for: n! n choose p = ----------- p! (n-p)! Enjoy! -K |
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