Solved UPSC CDS/OTA Question
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Q · AgeDifficult · 45s
5 years ago, the ratio of the ages of A and B was 7:5. The sum of their present ages is 46 years. Find A’s present age.
TopicAge
Question Typemultiple choice
DifficultyDifficult
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.
Let A's current age be a, and B's be b. Given: a + b = 46 → so b = 46 – a
Five years ago: A’s age = a – 5 B’s age = b – 5 = 41 – a Ratio: (a – 5)/(41 – a) = 7/5
Cross-multiply: 5(a – 5) = 7(41 – a) → 5a – 25 = 287 – 7a → 12a = 312 → a = 26
A’s present age is 26 years.
Final Answer: Option C - 26