The age of father 10 years ago was thrice the age of his son. Ten years hence, father's age will be twice that of his son. The ratio of their present ages is:

A. 5 : 2 B. 7 : 3

C. 9 : 2 D. 13 : 4

• Let the present ages of father and son be x and y years respectively.
  Then (x-10) = 3 (y-10) or
  3y-x = 20 ------ (1)
  and (x+10) = 2 (y+10) or
  x-2y = 10 ----- (2)
  (1) + (2) -> y = 30
  Substituting y = 30 in equation (1) we get x = 70
  Ratio of their ages = 70 : 30 or 7:3
• 12 years agoHelpfull: Yes(7) No(3)
• B as you can make eaquation of 10 years by considering present age to be X and Y
  so,
  Y-10=3(X-10)
  Y+10=2(X+10)
  By solving you will get 7/3.
• 9 years agoHelpfull: Yes(0) No(0)