okay, i'm stuck on a couple questions... :/
2!n! / 4!(n-5) = (n-1)! / (n-4)!
and..
(n+2)! / n! = 30
any help would be great, thanks!
I assume the red factorial was meant to be there.
This re-arranges into $\displaystyle \frac{2!}{4!} = \frac{(n-1)! (n-5)!}{n! (n-4)!}$.
The left hand side is 1/12. Simplify the right hand side using what you have learned from this thread (and what you should have learned from class too) and solve the resulting equation.