Question

A man is thrice as old as his son. After $12$ years, he will be twice as old as his son at that time. Find their present ages.

Answer 1

Let the present age of the son $=x$ years
and the present age of the father $=3x$ years
After $12\text{years}$,
Son’s age will be $(x+12)\text{years}$
and father’s age will be $(3x+12)\text{years}$
According to the condition,
$3x+12=2(x+12)$
$3x+12=2x+24$
$3x–2x=24–12$
$x=12$
$\therefore$ Present age of the son $=12\text{years}$
Present age of the father $=3\times 12\text{years}=36\text{years}$