Question

The sum of the ages of father and his son is 45 years five years ago the product of their age in year was 124 determine their present age

Answer 1

Let the age of son be x

so age of father will be 45-x as their sum of ages is 45.

5 years ago:

age of son will be x-5

age of father will be 45 -x -5= 40-x

According to question;

(x-5)×(40-x) = 124

so, 40x - x^2 -200 + 5x = 124

or, x^2 -45x +324 = 0

or, x^2 - 36x - 9x + 324 =0

or, x(x-36)-9(x-36) = 0

or, (x-36)(x-9) =0

so, x = 9 & 36{neglected as sum is just 45 }

So, age of son is 9 year.

and age of father is 36 years.