Question

Five years ago, a father was 3 times as old as his son. Now, their combined ages amount to 110 years. Thus, the present age of the father is?

Answer 1

5 years ago:
son's age --- x
father's age -- 3x

now:
son's age = x+5
fathers's = 3x+5

x+5 + 3x+5 = 110

solve for x, then sub into 3x+5