Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ - decoded step-by-step.
Solve it the standard way once - then learn the shortcut.
Q · AgeModerate · 45s
6 years ago, the ratio of the ages of A and B was 4:3. The sum of their present ages is 40 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 = 40 → so b = 40 – a
Six years ago: A’s age = a – 6 B’s age = b – 6 = 34 – a Ratio: (a – 6)/(34 – a) = 4/3
Cross-multiply: 3(a – 6) = 4(34 – a) → 3a – 18 = 136 – 4a → 7a = 154 → a = 22
A’s present age is 22 years.
Final Answer: Option C - 22