Three pipes, A, B and C, can fill a cistern in 12, 18 and 24 minutes, respectively. If all the pipes are opened together for 7 minutes, what will be the volume of the water that overflows as the percentage of the total volume of the cistern?
Show answer & explanation
Correct answer: A
Explanation
Correct Answer is option 1 i.e. 
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Understanding |
Application |
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Three pipes, A, B and C, can fill a cistern in 12, 18 and 24 minutes, respectively. |
Suppose the capacity of the cistern = 72 units (LCM of 12, 18 and 24) |
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Efficiency = Work/Time |
So, Efficiency of A = 72/12 = 6 Efficiency of B = 72/18 = 4 Efficiency of A = 72/24 = 3 |
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All the pipes are opened together for 7 minutes. |
So, Amount of water filled = (6 + 4 + 3) × 7 = 91 units |
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Hence, Number of units overflowed = 91 – 72 = 19 units |
Hence, Required percentage = 19/72 × 100 = |