Question

N! (N-4)! %(n-3)! (N-1)! =4

Answer 1

$\dfrac{n!(n-4)!}{(n-3)!(n-1)!}=4\\\\\dfrac{n(n-1)!(n-4)!}{(n-3)(n-4)!(n-1)!}=4\\\\\dfrac{n}{n-3}=4\\\\n=4n-12\\\\-3n=-12\\\\n=4$