Question

Use the permutation formula below to find the number of outcomes when n = 5 and r = 2.

Answer 1

$nPr = \frac{n!}{(n - r)!}$

$5P2 = \frac{5!}{(5 - 2)!} = \frac{5 \times 4 \times 3 \times 2 \times 1}{3 \times 2 \times 1} = 20$