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erby
08-12-2005, 12:10 AM
Pretty decent at math here, but I am having trouble with the technical vocab (i.e. C(6,2) and other stuff like that). Anyone have a link to definitions of these shorthand notations?

LetYouDown
08-12-2005, 08:52 AM
C(N,R) is the number of ways to choose R items from N items...regardless of order.

C(N,R) = N!/[(N-R)! * R!)]

P(N,R) is the number of ways to choose R items from N items...where each order is different.

P(N,R) = N!/(N-R)!

AaronBrown
08-12-2005, 07:13 PM
To expand on LetYouDown's excellent answer:

C(6,2) can be evaluated in Excel as =COMBIN(6,2)

A math major will read it "6 choose 2" and write it with the 6 above the two, like a fraction with no line separating the numbers, and round brackets around it.

erby
08-14-2005, 08:08 AM
Thanks guys. My roommate up at Princeton is a math major, and I always look at his books cuz the topics are so awesome, but i often lose out simply because i don't understand these notations. Is there some book that i can get? Maybe i should just ask my roommate... You guys have been very helpful