Two-condition age puzzle (father and son): Solve simultaneous relations to find the son's age. Now: Father's age = 3 × son's age. Five years ago: Father's age = 4 × son's age. Find the son's present age (in years). Choose the correct value.
Verbal Reasoning
Arithmetic Reasoning
Difficulty: Easy
Choose an option
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A12
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B15
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C18
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D20
Answer
Correct Answer: 15
Explanation
Let Son = s, Father = 3s.
Translate the past condition Five years ago: (3s − 5) = 4(s − 5).
Solve 3s − 5 = 4s − 20 ⇒ −5 + 20 = 4s − 3s ⇒ s = 15.
Check Now: Father = 45, Son = 15. Five years ago: 40 and 10 ⇒ 40 = 4 × 10 ✔