The sum of the ages of a son and father is 65 years. After 5 years the age of father will be double of the age of son. What is the age of son ?

• A. 18 years
• B. 17 years
• C. 20 years
• D. 19 years

Answer: (D)

Let the age of the son be x and the age of the father be y.Therefore, x + y = 65          ..........(i)or, 2 x (x + 5) = (y + 5)or, 2x + 10 = y + 5or, 2x - y = 5 ...................(ii)From equations (i) and (ii), x = 20, y = 45