Solved UPSC CDS/OTA Question
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Q · Time and WorkMedium · 45s
A leak can empty a full tank in 30 hours. An inlet can fill the same tank in 10 hours. If both are opened when the tank is empty, how long will it take to fill the tank?
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.
Net rate = 1/10 - 1/30 = (3-1)/30 = 1/15 → Time = 15 hours.
Final Answer: Option B - 12 hours