(a) Ratio of father’s present age to that of son = 42/14 = 3/1 = 3 : 1
(b) When son was 12 years, i.e., 2 years ago, then father was (42 – 2) = 40 years
Therefore, the ratio of their ages = 40/12 = 10/3 = 10:3
(c) Age of father after 10 years = 42 + 10 = 52 years
Age of son after 10 years = 14 + 10 = 24 years
Therefore, ratio of their ages = 52/24 = 13/6 = 16:6
(d) When father was 30 years old,
i.e., 12 years ago, then son was (14 – 12) = 2 years old
Therefore, the ratio of their ages = 30/2 = 15/1 = 15:1

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