Question

please answer this question​

Answer 1

at present:

let x=son's age

30+x=father's age

...

12 years hence:

x+12=son's age

30+x+12=42+x=father's age

...

42+x=3(x+12)

42+x=3x+36

2x=6

x=3

30+x=33

...

son's present age=3

father's present age=33