Question

Hello! May I please have some help on this one? I worked it out but my answer is wrong.

Answer 1

SOLUTION

Arranging r books from n books is given as n permutation r

$\begin{gathered} ^nP_r\text{ is the number of ways of arranging r books from n books } \\ \\ n=10 \\ r=4 \\ \\ ^{10}P_4=5040\text{ \lbrack input into calculator \rbrack} \end{gathered}$