Question

A man is 4 times as old as his son. In 5 years time he will be 3 times as old as his son. What is the present age of the son in years.​

Answer 1

Answer: 40 years old.

Explanation:

Let man's age = a

Let son's age = b

Since a man is 4 times as old as his son, therefore

a= 4b

In 5 years, he will only be 3 times as old as his son, therefore

a+5=3(b+5)

Apply substitution method :

4b+5=3b+15

b=10

a=40