Solved UPSC CDS/OTA Question
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Q · AgeModerate · 45s
4 years ago, the ratio of the ages of A and B was 5:4. The sum of their present ages is 35 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 = 35 → so b = 35 – a
Four years ago: A’s age = a – 4 B’s age = b – 4 = 31 – a Ratio: (a – 4)/(31 – a) = 5/4
Cross-multiply: 4(a – 4) = 5(31 – a) → 4a – 16 = 155 – 5a → 9a = 171 → a = 19
A’s present age is 19 years.
Final Answer: Option B - 19