Multiple choice

In a family, the ratio of the present ages of son, mother, father and grandfather is 1 : 4 : 5 : 11. The average age of son, mother and father is 20 years. What is the age of grandfather?

  1. 88 years

  2. 77 years

  3. 55 years

  4. 66 years

  5. 99 years

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let the present age of son be 1x years, that of mother be 4x years, that of father be 5x years and that of grandfather be 11x years. According to question, (1x + 4x + 5x)/3 = 20 x = 6 So, present age of grandfather = 11 x 6 = 66 years