Pipes & Cisterns · Question 14 · Hard
Pipes & Cisterns question 14
A tank is half full. An inlet can fill the whole tank in 8 minutes and an outlet can empty the whole tank in 12 minutes. If both are opened now, how long will it take for the tank to become full?
- 4 minutes
- 24 minutes
- 12 minutes
- 6 minutes
Answer and explanation
Answer: C. 12 minutes
Explanation: Net filling rate = 1/8 − 1/12 = 1/24 of the tank per minute. Half the tank needs (1/2) ÷ (1/24) = 12 minutes.
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