7 is added to a certain number; the sum is multiplied by 5 ; the product is divided by 9 and 3 is subtracted from the quotient. Thus, if the remainder left is 12, what was the original number ?

A. 20

B. 30

C. 40

D. 60

Answer: Option A

Solution(By Examveda Team)

Let the original number be x.
Then,
$$\frac{(x + 7) × 5}{9}$$   - 3 = 12
⇒ $$\frac{5x + 35}{9}$$  = 15
⇒ 5x + 35 = 135
⇒ 5x = 100
⇒ x = 20