Question

I am three times as old as my son 15 years hence,i will be twice

Answer 1

let the age of son be x years.
father's age is 3x.
After 15 year
2(x+15)= (3x+15)
2x+30 = 3x+15
x=15

son age = 15
father age = 45

Answer 2

Answer:

In simple without formula

15 X 3 = 45 + 15 = 60