You can put this solution on YOUR website! father is 61 yrs
and son is 16 yrs
as per conditions in how many years father will be two times son age
let x years after
father =61+x
son = 16+x
61+x= 2(16+x)
61+x =32+ 2x
2x-x=61-32 =29
yrs
answer after 29 yrs father will be twice of son age