Let’s assume the present ages of the father as a years and that of his son’s age as b years.

From the question it’s given that,

Father is 3 times as old as his son. (Present)

So, the equation formed is

⇒ ……. (I)

Now from the given question is,

After 12 years, father’s age will be years and son’s age will be years.

so, the relation between their ages after 12 years is given below

⇒

⇒ …… (ii)

Solving (i) and (ii), we get the solution

By using cross-multiplication, we have

,

So, the present age of father is years and the present age of son is years.