The father's present age is 42 years and that of his son is 14 years. Find the ratio of the age of father to son, when the son was 12 years old.
10:3
When the son was 12 years, i.e., 2 years ago, father's age would have been (42 - 2) = 40 years.
Therefore, the ratio of their ages = 4012 = 103 = 10:3.