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Q: Three pipes, A, B, C can fill an empty cistern in 2, 3 and 6 hours respectively. They are opened together. After what time should B be closed, so that the cistern gets filled in exactly 1hr 15min?
  • A. 15 minutes
  • B. 20 minutes
  • C. 45 minutes
  • D. 30 minutes
Correct Answer: Option D -
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Explanations:

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