Solved UPSC CDS/OTA Question
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Q · AgeDifficult · 45s
4 years ago, the ratio of the ages of A and B was 5:4. The sum of their present ages is 44 years. Find B’s present age.
TopicAge
Question Typemultiple choice
DifficultyDifficult
Marking+1 / −0.33
From TestChapter Test 1 (Chapter Test)
Test Duration30 min
← Previous questionQ 52 / 52
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. 4 years ago, their ages were a–4 and b–4, and the ratio was 5:4. So: (a–4)/(b–4) = 5/4 → cross-multiplies to 4a – 5b = –4. Also, a + b = 44.
Substitute a = 44 – b into the first equation: 4(44 – b) – 5b = –4 → simplify to get b = 24.
Final Answer: Option D - 24