Answer :

**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**

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Which of the following are true :

(2 + 3)! = 2! + 3!

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