Question

If 11 Pr = 990 firnd r

Answer 1

11 Pr = 990 
Pr = 990/11 = 90
therefore,
r = 90/P

Answer 2

Answer:

r=3

Step-by-step explanation:

Given : $_{11}P_r=990$

To Find: r

Solution :

We are given

$_{11}P_r=990$

Now, To get factors of 990

11 | 990

10 |  90

9  |    9

   |     1

⇒ 990= 11*10*9

So,

$_{11}P_r=11\times10\times9$

$_{11}P_r=_{11}P_3$

On comparing we get r = 3

Hence if $_{11}P_r=990$ the value of r is 3.