5 years hence, the age of a man shall be 3 times the age of his son while 5 years earlier the age of the man was 7 times the age of his son. The present age of the man is

Options

A. 45 years
B. 50 years
C. 47 years
D. 40 years

Answer

D

Explanation

Let the present ages of the man and his son be x years and y years repectively. Then,
`(x + 5) = 3( y + 5) rArr x - 3y = 10" " `...(i)
` (x - 5) = 7(y - 5) rArr x - 7y = - 30 " " `... (ii)