Solved UPSC CDS/OTA Question
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Q · Time and WorkMedium · 45s
An inlet pipe can fill a cistern in 6 hours, but due to a leak it takes 8 hours to fill. How long will it take the leak alone to empty the full cistern?
TopicTime and Work
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.25
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Filling rate = 1/6, net rate = 1/8, leak rate = 1/6 - 1/8 = 1/24 → Leak alone empties in 24 hours.
Final Answer: Option B — 24 hours