The peresent age of the father and the son are in the ratio of 8:3. After 12 years the ratio of their ages will be 2:1. What is the sum of the present age of the father and the son ?

• A. 69 years
• B. 67 years
• C. 68 years
• D. 66 years

Answer: (D)

Let the present age of the father be 'x' and that of the son be 'y'. Then x/y = 8/3∴ 3x = 8y Further, x + 12/y + 12 = 2/1 ∴ x + 12 = 2y + 24                                         ∴ x - 2y = 12        ......(ii)From eqn (i) and (ii), x = 48, y = 18                          ∴ sum = 66 yrs.