A tap can fill an empty tank in 12 h and a leakage can empty the tank in 20 h. If tap and leakage both work together, then how long will it take to fill the tank?

A) 25 h

B) 40 h

C) 30 h

D) 35 h

Correct Answer:
C) 30 h

Description for Correct answer:
Part filled by tap in 1 h =\( \Large \frac{1}{12} \)

Part emptied by leak in 1 h = \( \Large \frac{1}{20} \)

Net part filled in 1 h when both (tap and leakage) work

= \( \Large \frac{1}{12} \)-\( \Large \frac{1}{20} \)=\( \Large \frac{5-3}{60} \)=\( \Large \frac{2}{60} \)=\( \Large \frac{1}{30} \)

Therefore, Required time to fill the tank = 30 h

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


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