Question

Determine o valor de n em An,4/An,3=4.

Answer 1

An,p=n!/(n-p)!

fazendo por parte

An,4=n!/(n-4)!

An,3=n!/(n-3)! = n!/((n-3).(n-4)!)

An,4/An,3=(n!/(n-4)!)/(n!/((n-3)(n-4)!)

An,4/An,3 = n-3=4

n=4+3

n=7