Question

A man is 40 years old and his son is 5years old. In how many years will the father be 3 times the age of his son.

Answer 1

12 1/2 years

Explanation:

Let the unknown be n. Then 40+n = 3(5+n).

Performing the multiplication:

40+n = 15+3n

Isolate n and combine the constant terms:

25=2n, so n= 25/2 years