PakQuizHub

A single tap can fill a tank in 6 hours. Once the tank is half full, three additional identical taps are opened. How long will it take to fill the tank entirely?

Pipes and Cisterns MCQs for PPSC, FPSC, NTS, and Pakistan government job tests. Select an option below, then read the explanation.

Browse all Pipes and Cisterns MCQs →
PPSCFPSCNTSPakistan govt jobs
Subject
Pipes and Cisternsmathematics-mcqs › pipes-and-cisterns
Published
11 Jul 2019
Last updated
28 May 2026

Browse all Pipes and Cisterns MCQs →

Choose the correct answer

Explanation

The first tap fills half the tank in 3 hours (since it fills the whole tank in 6 hours). After that, four taps work together to fill the remaining half. The combined rate of four taps is four times that of one tap, so they fill the remaining half in 1.5 hours. Total time = 3 hours + 1.5 hours = 4.5 hours or 3 hours 45 minutes.

More Pipes and Cisterns MCQs

Practice related questions from the same subject.

  1. 1.Three taps A, B, and C can fill a tank in 12, 15, and 20 hours respectively. If tap A runs continuously while taps B and C operate alternately for one hour each, how long will it take to fill the tank completely?
  2. 2.A tank can be filled by one tap in 4 hours, while another tap can drain it in 9 hours. If both taps are opened at the same time, how long will it take to fill the tank completely?
  3. 3.A large tanker can be filled by pipe A alone in 60 minutes and by pipe B alone in 40 minutes. If pipe B runs for half the total filling time and then both pipes A and B operate together for the remaining half, how long will it take to fill the tanker completely from empty?
  4. 4.A tank is filled by two pipes, where the faster pipe fills it three times quicker than the slower one. If both pipes working together fill the tank in 36 minutes, how long will it take the slower pipe alone to fill the tank?
  5. 5.A tank usually fills up in 8 hours, but due to a leak at the bottom, it takes 2 hours longer to fill completely. How long will it take for the leak alone to drain the full tank?
  6. 6.A tank can be filled by one tap in 2 hours, while another tap can drain the tank in 3 hours. If both taps are opened simultaneously, how long will it take to fill the tank?
  7. 7.One tap can fill a tank in 8 hours, while another tap can drain it in 16 hours. If both taps are operated at the same time, how long will it take to fill the tank?
  8. 8.Pipes A, B, and C together can fill a tank in 6 hours. After operating all three for 2 hours, pipe C is turned off, and pipes A and B finish filling the tank in 7 more hours. How long will pipe C take to fill the tank by itself?
← Back to Mathematics Mcqs
More in Mathematics Mcqs

PakQuizHub — free MCQs and past papers for Pakistan government job tests. Content is for educational practice only.