Question

after 12 years Kanwar shall be three times as old as he was 4 years ago find his present age

Answer 1

Let present age of Kansas be x years
ATQ
x+12=3(x-4)
x+12=3x-12
2x=24
x=12

Answer 2

let present age=x.
age after 12 yrs=x+12.
age 4 yrs ago=x-4.

according to question.
3(x-4)= x+12.
3x-12=x+12.
3x-x=12+12.
2x=24.
x=24/2.
x=12.

So present age=12