Correct Answer - Option 4 : 87 years
Calculation:
Let be assume present age of A, B, and C is A, B, and C
⇒ (A - 6) = 2 × (B - 4) ---(1)
⇒ C = B + 9 ---(2)
⇒ C = A - 9 ---(3)
⇒ By solving equation (1), (2) and (3)
⇒ A = 38, B = 20, C = 29
⇒ The sum of present age of A, B, and C = A + B + C = 38 + 20 + 29 = 87
∴ The required result will be 87.