A father is twice his son’s present age. How many years ago, was he three times his son’s age, if his son’s age is now 20 years?

Given that :- Present age of son = 20 years According to question , father’s present age = 2 × Present age of son His father’s present age = 2 x 20 = 40 years 10 years ago , The age of son = 20 – 10 =10 years Father’s age = 40 – 10 = 30 years = 10 × 3 Hence , required answer will be 10 years ago .