Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ - decoded step-by-step.
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Q · AgeModerate · 45s
The sum of the ages of a father and his son is 60 years. Five years ago, the father's age was four times the son's age. Find the son's present age.
TopicAge
Question Typemultiple choice
DifficultyModerate
Marking+1 / −0.33
From TestChapter Test 1 (Chapter Test)
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained - no skipped algebra.
Use the condition from 5 years ago
Father's age 5 years ago = 60 – S – 5 = 55 – S
Son's age 5 years ago = S – 5 Given: Father’s age = 4 × Son’s age → 55 – S = 4(S – 5)
Solve the equation
55 – S = 4S – 20 → 55 + 20 = 4S + S → 75 = 5S → S = 15
Final Answer: Option A - 15 years