Bissoy.com
Doctors Medicines MCQs Q&A

Pipe A and Pipe B can together fill a tank in 4 hours. But, if pipe A was stopped for some time and then restarted, it took 6 hours to fill the tank. If pipe A is twice as efficient as pipe B, then for how much time was pipe A stopped?

Pipe A and Pipe B can together fill a tank in 4 hours. But, if pipe A was stopped for some time and then restarted, it took 6 hours to fill the tank. If pipe A is twice as efficient as pipe B, then for how much time was pipe A stopped? Correct Answer 3 hours

Let pipe B take ‘x’ hours to fill the tank alone

Part filled by pipe B in 1 hr. = 1/x

∵ Pipe A is twice as efficient as B, part filled by pipe A in 1 hr. = 2/x

Part filled by pipes A & B in 1 hr. = 1/x + 2/x = 3/x

But, together they can fill the tank in 4 hours,

⇒ 3/x = 1/4

⇒ x = 12

Part filled by A in 1 hr. = 2/x = 2/12 = 1/6

Part filled by B in 1 hr. = 1/12

Now, let pipe A be stopped for ‘t’ hours, then, work done in 6 hours is,

⇒ (6 – t) × 1/6 + 6 × 1/12 = 1

⇒ 1 – t/6 + 1/2 = 1

⇒ t/6 = 1/2

⇒ t = 6/2 = 3 hours

∴ Pipe A was stopped for 3 hours

Related Questions

In the following question, two statements are numbered as A and B. On solving these statements, we get quantities A and B respectively. Solve both quantities and choose the correct option. Quantity A: Pipe A takes thrice the time taken by Pipe B to fill a tank. Together they can fill the tank in 15 hours, tank A and B is opened together for 4 hours and then Pipe A is closed and after 2 more hours Pipe B is closed and an outlet Pipe C is opened which when working alone can empty the tank in 10 hours. Calculate the time taken by C to empty the tank. Quantity B: A pipe A can fill the tank in 10 hours another pipe B can fill the tank in 15 hours and with the help of third pipe C they can fill the tank in 5 hours. Pipe A is opened for 4 hours then it is closed, pipe B is closed 3 hours before filling of tank and tank C is opened the whole time. Calculate the time taken to fill the tank
In the following question, two statements are numbered as A and B. On solving these statements, we get quantities A and B respectively. Solve both quantities and choose the correct option. Quantity A: Pipe A takes thrice the time taken by Pipe B to fill a tank. Together they can fill the tank in 15 hours, tank A and B is opened together for 4 hours and then Pipe A is closed and after 2 more hours Pipe B is closed and an outlet Pipe C is opened which when working alone can empty the tank in 10 hours. Calculate the time taken by C to empty the tank. Quantity B: A pipe A can fill the tank in 10 hours another pipe B can fill the tank in 15 hours and with the help of third pipe C they can fill the tank in 5 hours. Pipe A is opened for 4 hours then it is closed, pipe B is closed 3 hours before filling of tank and tank C is opened the whole time. Calculate the time taken to fill the tank.
Three pipes x, y and z can fill a tank A can fill it in 4 minutes. Two pipes p and q are connected to tank B. how much time does it take for both tanks to run at the full capacity? Ratio of time taken to fill tank A by P and time taken by x to fill tank A is 2: 1 and ratio of time taken by Q to fill tank B and Z to fill tank A is 5: 3. Pipe P is 20% more efficient then pipe Q. and pipe Y takes 12 minutes to fill the tank. Capacity of tank B is 3/4 times of tank A. Note: Tank B is to be filled only after filling tank A. Valves of pipe p and q are closed once tank B is running at full capacity.
Two pipes are connected to tank 1 and one pipe connects tank 1 and tank 2 at the bottom of both tanks. At first pipe A and pipe B will filling tank 1 and then pipe C would be opened to fill tank 2. Capacity of tank 1 is twice capacity of tank 2. Pipe C takes 8 minutes to fill the whole tank 2 wherein discharging capacity of pipe C is 62.5 liters per minute. Ratio of time taken by pipe A and B to fill the tank when operating alone is 4 : 5 then find approximate discharging capacity of pipe A and B in liters/ minute if both the pipes discharge equal amount of water in tank. Time taken by pipe A and B to fill the tank 1 is 20/ 3 minutes
In the following question, two statements are numbered as A and B. On solving these statements, we get quantities A and B respectively. Solve both quantities and choose the correct option. Quantity A: There are two inlet pipes A, B and two outlet pipes C, D inlet pipe B takes 7 hours more to fill the tank when compared to A. Two outlet pipes when working together can empty the tank in 3.5 hours and efficiency of both the pipe is same if all of them working together can fill the tank in 2 hours. Calculate the time taken by A to fill the tank. Quantity B: The ratio of efficiencies of two pipes A and B is in the ratio 3 ∶ 2 and that of pipe B and C is 1 ∶ 3. Pipe A and B are inlet pipes, pipe C is outlet pipe working together they can fill the tank in 7.5 hours. Calculate the time taken by A to fill the tank when working alone.
A tank can be filled using pipes A, B, and C and can be emptied using pipe D. Pipes A & B can together fill the tank in 8 hours, pipes B & C can together fill the tank in 10 hours and pipes A & C can together fill the tank in 6 hours. If pipe D can alone empty the tank in 15 hours, in how much time will the tank be filled if all the pipes are simultaneously opened?
Given below are quantities named A,B and C. Based on the given information, you have to determine the relation between the quantities. You should use the given data and your knowledge of mathematics to choose among the possible answer. Quantity A: Tap1 and Tap2 can fill the tank in 16 hours and 25 hours respectively. Both the taps opened together. After some time Tap 1 is closed and after that the tank is filled in 12 hours. In how many hour Tap 1 and 2 work together? Quantity B: Three taps 1, 2, 3 can fill a cistern in 10,14,18 hours respectively. If tap 1 is kept open all the time and tap 2 and 3 is opened alternatively for an hour then find in how many hours the tank will be filled? Quantity C: Two taps 1 and 2 are such that tap 1 fills the tank in 10 hours and tap2 empties it in 20 hours. If tap 1 is opened first and after 5 hours tap 1 is closed and tap 2 is opened, then the tank emptied in x hours and find the value of x?
Pipes A and B are used to fill the tank. A can fill the tank twice as fast as B. Pipe C and D can empty the tank. D takes same time to empty the tank as taken by B to fill it. Pipe C can empty tank in 6 hours. If all 4 are opened together, how much hour would it take to fill the tank? (Assume: D can empty tank twice as fast as C.)
In the following question, two quantities I and II are given. Compare both quantities and choose the correct option and give the answer accordingly. Quantity I: Two taps A and B can fill a tank in 5 hours and 20 hours respectively. If both the taps are open then due to leakage, it took 30 minutes more to fill the tank. If the tank is full, how long will it take for the leakage alone to empty the tank? Quantity II: A tank is filled in 5 hours by three pipes A, B and C. The pipe C is twice as fast as B and B is twice fast as A. How much time will pipe A alone take to fill the tank?
In the following question, two statements are numbered as A and B. On solving these statements, we get quantities A and B respectively. Solve both quantities and choose the correct option. Quantity I: Pipe A alone can fill the tank in 15 hours while pipe B alone can empty the tank in 5 hours. There is a leakage at the bottom which also alone can empty the tank in 4 hours. When pipe A and Pipe B are open simultaneously then in how many hours the tank gets empty? Quantity II: 25 men can complete the work in 20 hours and 30 women can complete the work in 15 hours. If 15 men work for 10 hours then stopped working then remaining work gets completed by all 30 women. In what time total works get completed?