The age of a man is three times the sum of the ages of his two sons. Five years hence, his age will be double of the some of the ages of his sons. The father’s present age is : Choose the correct choice from the following answers.
A) 29 years  B) 36 years  C) 42 years  D) 45 years  E) None
Sol.   Let the sum of present ages of the two sons be x years.   Then, faher’s present age = 3x years.   ∴ (3x + 5) = 2 (x + 10) ⇔ 3x + 5 = 2x + 20 ⇔ x = 15.   Hence, father’s present age = 45 years.   Answer 45 years
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The age of a man is three times the sum of the ages of his two sons. Five years hence, his age will be double of the some of the ages of his sons. The father’s present age is :