Question 324356
let the age of son be x
father's age = 55-x
..

after 16 years their ages will be:
son x+16
father 55-x+16= 71-x
..
Father's age = twice son's age
71-x= 2(x+16)
71-x = 2x +32
3x= 71-32
3x=39
x=13 years , son's age
Father's age = 55-x
= 55-13
=42 years

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