Mathematics
NULL
Medium
Question
Pipe A fills in 5 hours, B in 10 hours and C in 30 hours. If all are open, in how many hours will the tank be filled?
A
2
B
2.5
C
3
✓ Official correct answer
D
3.5
Community credibility
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A
2
No member explanations yet for this option.
B
2.5
No member explanations yet for this option.
C
3
No member explanations yet for this option.
D
3.5
No member explanations yet for this option.
Explanation
Rate = 1/5 + 1/10 + 1/30 = 1/3. Time = 3 hours.