Multiple choice

Five years ago the sum of ages of the father and the son was $40$ years. At present, the ratio of their ages is $4: 1$. The present age of father is:

  1. $30$ years
  2. $40$ years
  3. $45$ years
  4. $42$ years
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let F and S be current ages. (F-5) + (S-5) = 40 => F + S = 50. F/S = 4/1 => F = 4S. 4S + S = 50 => 5S = 50 => S = 10. F = 40.

AI explanation

Let the present ages of the father and son be 4x and x years respectively. Five years ago, their combined age was 40, so their present combined age is 50, giving the equation 4x + x = 50. Solving this yields 5x = 50 and x = 10. Therefore, the present age of the father is 4 multiplied by 10, which is 40 years.

Keep practicing — related questions