Question

The age of a father is 2 less than 7 times the age of his son. In 3 years, the sum of their ages will be 52. If the son’s present age is s years, which equation models this situation?

Answer 1

The father is 40 which is 2 less than 7x6=42 Therefore the son is 6. In 3 years the the father will be 43 and the son will be 9. 43+9=52

Answer 2

Son’s present age, s = 6 years.

Explanation:

Let the son’s present age is s years and father's be f.

We have age of a father is 2 less than 7 times the age of his son.

f = 7s -2

7s - f = 2 -------------------eqn 1

In 3 years, the sum of their ages will be 52.

s + 3 + f + 3 = 52

s + f = 46 -------------------eqn 2

eqn 1 + eqn 2

8s = 48

s = 6

Son’s present age, s = 6 years.