Question

How do you evaluate `""_7P_3`?

Answer 1

210

Explanation:

The general formula for a permutation is:

`P_(n,k)=(n!)/((n-k)!)`; `n="population", k="picks"`

and so:

`P_(7,3)=(7!)/((7-3)!)=(7!)/(4!)=(7xx6xx5xx4!)/(4!)=7xx6xx5=210`