Given: P(9, r) = 3024

To find: value of r

We know,

So, according to question:

P(9, r) = 3024

⇒ (9 – r)! = 5!

⇒ 9 – r = 5

⇒ -r = 5 – 9

⇒ -r = -4

∴ The value of r = 4