The present age of a father is years more than thrice the age of his son. years hence ,the father will be years more than twice the age of his son. After how many years, the fathers age will be double the age of the son?
Step 1: Assuming the present ages of father and son by variables
Let the present age of father be years and that of son be years.
Step-2 Framing the equations to find their present ages
Case 1
Case 2
Substituting (1) in (2)
Therefore the present age of father =33 years and that of son =10 years
Step-3: Applying condition for fathers age after ‘n’ years
Let after ‘’ years, the fathers age will be double of the age of the son.
After ‘’ years,
father's age =
son's age=
Given,
Therefore after 13 years, father's age will be double of sons age.
Checking
after 13 years,
father's age =
son's age =