Ten years ago a man was three times as old as his son. In twelve more years, the son is three-fifths as old as his father. What were their ages 5 years ago?

1 answer

if the man is now m and the son s,

m-10 = 3(s-10)
(3/5)(m+12) = s+12

m-5 = 38
s-5 = 16