Question

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

• 45 years

• 50 years

• 47 years

• 40 years

Answer 1

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 40 years.

Explanation:

Let the man’s present age = x and his son’s = y. 

From 5 years hence: 

x + 5 = 3(y + 5) 

⇒ x – 3y = 10

From 5 years earlier: 

x – 5 = 7(y – 5) 

⇒ x – 7y = –30

Subtracting gives 4y = 40

⇒ y = 10

So, x = 3 × 10 + 10 

= 40 years