Question

5 years ago, the sum of ages of father and his son was 30 years. 3 years hence the sum of their ages would be ......... years

Answer 1

Let current age of father =x
and,
Age of son =y

5 years ago their ages would be,
x-5 and y-5
Given the sum of ages 5 years ago is 30
Ie,
(x-5 )+ (y-5)= 30
x+ y =30+5+5
x+y =40

We need to find the sum of ages after 3 years.
3 years from now, their ages would be,
x+3 and y+3
So the sum of ages,
=(x+3)+(y+3)
=x+y +3+3
=x+y+6. ____________eqn 1
We know,
x+y=40
Substitute in eqn 1,
=40+6
=46

So the answer is 46