Mathematics
NULL
Medium
Question
The water in a rectangular reservoir 80 m by 60 m is 6.5 m deep. In what time can it be emptied by a square pipe of side 20 cm if water runs at 15 km/h?
A
26hours
B
42hours
C
52hours
✓ Official correct answer
D
65hours
Community credibility
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A
26hours
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B
42hours
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C
52hours
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D
65hours
No member explanations yet for this option.
Explanation
Volume = 80×60×6.5 = 31,200 m³. Pipe area = 0.04 m²; speed = 15,000 m/h. Time = 31200/(0.04×15000) = 52 hours.