Solved UPSC CDS/OTA Question
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Q · AgeModerate · 45s
10 years ago, the ratio of the ages of A and B was 3:2. The sum of their present ages is 30 years. Find A’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.
Let A's current age be a, and B's be b. Given: a + b = 30 → so b = 30 – a
Ten years ago: A’s age = a – 10 B’s age = b – 10 = 20 – a Ratio: (a – 10)/(20 – a) = 3/2
Cross-multiply: 2(a – 10) = 3(20 – a) → 2a – 20 = 60 – 3a → 5a = 80 → a = 16
A’s present age is 16 years.
Final Answer: Option C - 16