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# 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

 C) 30 h

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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