Question

If 10Px = 5040, then find the possible value of x. 4 3 5 6


I really need help on this its called permutations!

Answer 1

5040=10px
5040÷10=504
504÷9=56
56÷8=7
《X=4》
10×9×8×7=5040
It's permutation prblm

Answer 2

Answer:

x=4

Step-by-step explanation:

Given :  10Px = 5040

To Find: x

Formula of permutation : $_nP_r =\frac{n!}{(n-r)!}$

Comparing with the given expression with the formula

n=10 r=?  

So,putting values in formula

5040= 10!/(10-r)!

⇒7! = 10!/(10-r)!

⇒(10-r)!=  10!/7!

⇒(10-r)!= 10*9*8*7!/7!

⇒(10-r)!=10*9*8

⇒(10-r)!=720

⇒(10-r)!=6!

⇒10-r=6  

⇒r=10-6

⇒r=4

Thus value of r = x = 4