Mathematics
Medium
Question
Two pipes P and Q can fill a cistern in 12 and 15 minutes respectively. Both are opened together, but at the end of 3 minutes the first is turned off. How much longer will the cistern take to fill?
A
9 1/4 min
B
11 1/4 min
✓ Official correct answer
C
7 1/4 min
D
8 1/2 min
Community credibility
Registered members can vote for the answer they believe is correct today and explain why. If the facts change after an election or news event, suggest a new option so others can vote it up.
A
9 1/4 min
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B
11 1/4 min
No member explanations yet for this option.
C
7 1/4 min
No member explanations yet for this option.
D
8 1/2 min
No member explanations yet for this option.