Answer
20
Work Step by Step
Use the formula of permutation: $_{n}$P$_{r}$=$\frac{n!}{(n-r)!}$. Plug in 5 for N and 2 for R:
$_{n}$P$_{r}$=$\frac{n!}{(n-r)!}$
$_{5}$P$_{2}$=$\frac{5!}{(5-2)!}$ -simplify-
$_{5}$P$_{2}$=$\frac{5!}{3!}$ -write using factorial-
$_{5}$P$_{2}$=$\frac{5*4*3*2*1}{3*2*1}$ -simplify-
$_{5}$P$_{2}$=20
