Pipes & Cisterns · Question 4 · Easy
Two pipes fill a cistern in 12 minutes and 20 minutes respectively. What fraction of the cistern is filled in 3 minutes when both are open?
- 3/8
- 1/4
- 1/2
- 2/5
Answer and explanation
Answer: D. 2/5
Explanation: Together they fill 1/12 + 1/20 = 8/60 = 2/15 per minute. In 3 minutes: 3 × 2/15 = 2/5.
Previous: A pipe fills a 1,200-litre tank in 4 hours. At the same rate, how many litres… · Next: A leak at the bottom of a full tank empties it in 8 hours. What part of the…
Practise pipes & cisterns
Try a fresh set of pipes & cisterns questions with an explanation after every answer, free and without signing up: Pipes & Cisterns practice. Or sit a full placement mock test.
More pipes & cisterns questions
- Pipe A can fill a tank in 10 hours and pipe B can fill it in 15 hours. If both…
- A tap fills a tank in 6 hours, while an outlet empties the full tank in 9…
- A pipe fills a 1,200-litre tank in 4 hours. At the same rate, how many litres…
- A leak at the bottom of a full tank empties it in 8 hours. What part of the…
- A pipe can fill a tank in 4 hours. Because of a leak, it takes 5 hours to…
- Pipes A and B fill a tank in 20 minutes and 30 minutes respectively, and pipe…
- Pipes P and Q can fill a tank in 12 hours and 18 hours. Both are opened for 4…
- One pipe fills a tank three times as fast as another. Together they fill it in…
- An outlet can empty a full tank in 10 hours. If an inlet that lets in 6 litres…
- Pipes A and B can fill a tank in 15 minutes and 20 minutes. Both are opened…
More quantitative aptitude practice
Time, Speed & Distance · Problems on Trains · Boats & Streams · Permutation & Combination · Probability · Data Interpretation · Mensuration · Algebra & Equations
LogicWiz Exams home · All practice topics · Placement mock tests · Daily 10 challenge