Pipe A fills a tank in 24 minutes. Pipe B can fill the same tank 7 times as fast as Pipe A. If both the pipes are kept open when the tank is empty, when will the tank be full?


A) 5 minutes

B) 2 minutes

C) 4 minutes

D) 3 minutes

Correct Answer:
D) 3 minutes

Description for Correct answer:
Pipe B will fill the tank in \( \Large \frac{24}{7} \) minutes as it is 7 times as fast as Pipe A.

Together, the two pipes will fill \( \Large \frac{1}{24}+\frac{7}{24}=\frac{8}{24}=\frac{1}{3} \)rd of the tank in a minute.

So, it will take 3 minutes for the tank to overflow.

Part of solved Pipes and Cisterns questions and answers : >> Aptitude >> Pipes and Cisterns








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