# simplifying an expression

• Mar 18th 2011, 11:12 PM
ulysses123
simplifying an expression
I have an expression for a conditional probability with the following term:

N!/n!(N-n)!

I can't remember how to simplify this i know that it is (N choose n )*1/n! but can it be simplified further?
• Mar 18th 2011, 11:16 PM
matheagle
${N\choose n}$ is ${N!\over (N-n)!n!}$

so I don't know what you're asking, why don't you state the entire problem.
• Mar 18th 2011, 11:40 PM
ulysses123
Yes its N choose n, i got it now i was confusing myself after looking at the problem for a while