Solved UPSC CDS/OTA Question
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Q · Time and WorkMedium · 45s
A cistern has two pipes. One can fill it with water in 8 hours and another can empty it in 5 hours. In how many hours will the cistern be emptied if both the pipes are opened together when ¾ of the cistern is already full of water?
TopicTime and Work
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.25
Test Duration30 min
Step-by-Step Solution
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Final Answer: Option A — 6 h