Bissoy.com
Doctors Medicines MCQs Q&A

A pipe can fill a tank in 20 mins and another pipe can fill a tank in 30 mins. Pipe A is opened for half of the time and B and A are opened for the other half. How long will it take to fill the tank?

A pipe can fill a tank in 20 mins and another pipe can fill a tank in 30 mins. Pipe A is opened for half of the time and B and A are opened for the other half. How long will it take to fill the tank? Correct Answer 15

Given:

A pipe can fill a tank in 20 mins and another pipe can fill a tank in 30 mins. Pipe A is opened for half of the time and B and A are opened for the other half

Calculation:

Part filled by A in 1 min = 1/20

Part filled by B in 1 min = 1/30

Let the time taken to fill the tank be x mins.

According to the question,

{(1/20)(x/2)} + {(1/20 + 1/30)(x/2)} = 1

⇒ x = 15 mins

∴ The required time is 15 mins.

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.
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
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.
Given below are three quantities named A, B and C. Based on the given information; you have to determine the relationship between the two quantities. You should use the given data and your knowledge of Mathematics to choose between the possible answers. The options represent the relations between these three quantities A) > B) < C) = D) ≤ E) ≥ Two pipes P and Q can fill an empty tank in 20 minutes and 30 minutes respectively. Quantity A: If both pipes are opened simultaneously, then after what certain time P should be closed so that further time after which the tank is filled in 15 minutes? Quantity B: If both are opened and P is closed after 8 minutes, how much further time would it take for Q to fill the bucket? Quantity C: Pipe A and B can fill a tank in 15 minutes and 10 minutes respectively. Pipe C can empty the tank in 5 minutes. Pipe A and B are opened simultaneously and after the 4-minute pipe, C is also opened. In what time the tank will be emptied?
There are two pipes T and V which can empty the tank and one pipe S can fill the tank. Pipe S can fill the tank in 5 hours. Pipe T can empty half of the tank in 5 hours. Pipe S is opened for 1 hour and 15 min then Pipe T and Pipe V are also opened. Then the (remaining) tank gets filled in 10 hours. In what time pipe V can empty the 1/4th filled tank?
The question below is followed by three statements I, II, and III. You have to determine whether the data given is sufficient for answering the question. You should use the data and your knowledge of mathematics to choose the best possible answer. A water tank is to be filled. Pipe A is opened for 10 minutes and then closed. After that pipe, B is opened and the remaining tank is filled by Pipe B alone. In how much time pipe B filled the remaining tank working alone? I. Pipe A and B together can fill a tank in 12 minutes. II. Pipe B, C, can fill a tank in 10 minutes. The ratio of their efficiency is 1 : 2 III. Pipe D and C can fill a tank in 12 minutes
Time taken by pipe A and pipe B to fill up the cistern is 12 minutes whereas time taken by pipe C to empty the whole cistern is twice that of time taken by A and B together to fill the tank and ratio of time taken by pipe A and B to fill up the tank when operating alone is 2 : 3. If pipe A and B are alternatively opened every 6 minutes and C is opened with pipe B but closed when pipe A is opened then calculate total time taken to fill up the whole cistern. 
Four pipes P, Q, R and S are connected to a tank. Pipe P, Q, R and S can fill the whole tank in 300/37 minutes. Ratio of time taken by pipe P to fill the tank when operating alone and pipe Q to fill the tank when operating alone is 3 : 2, pipe Q is 20% more efficient then pipe R and time taken by pipe S is 10 minutes more than pipe R. Find difference between time taken by pipe Q and pipe P to fill up the tank alone. 
To fill the tank Pipe A and Pipe B takes 12hours. Pipe B and Pipe C takes 9 hours to fill the tank and Pipe C and Pipe A together take 15 hours to fill the tank. Find the time taken to fill the tank when Pipe A, Pipe B and Pipe C opened together(approximately).