After adding 7 to a number, the sum is multiplied by 5, and the product so obtained is divided by 9. From the quotient so obtained. 3 is subtracted to get 12. The number is:

Correct option is B

Given:

After adding 7 to a number the sum is multiplies by 5 the product is divided by 9

From the quotient so obtained 3 is subtracted to get 12

Solution:

Let the number be x

Then if 7 is added to the number then number becomes x +7

Number than multiplied by 5 = 5(x+7)

If resultant is divided by 9 then from quotient 3 is subtracted

​$$\frac{5(x+7)}{9} -3 = 12$$​​

​$$\frac{5(x+7)}{9} = 12 +3$$​​

​$$5(x+7) =9(15)$$​​

​$$x+7 = \frac{135}{5}$$​​

​$$x+7 = 27$$​​

​$$x=27-7 =20$$​​