Question

Hello, can you please help me with question number 1? use the formula for nPr to evaluate each expression:9P4

Answer 1

Case: Permutation

nPr=

`^nP_r=(n!)/((n-r)!)`

Method:

`\begin{gathered} ^9P_4=(9!)/((9-4)!) \\ =(9!)/(5!) \\ =9*8*7*6*(5!)/(5!) \\ =9*8*7*6 \\ =3024 \end{gathered}`

Final answer:

9P4= 3024