Pipes and Cistern

A swimming pool has $3$ drain pipes. The first two pipes A and B, operating simultaneously, that of taken by C alone. Pipe A, working alone, takes half the time taken by pipe B. Together they take $6$ hrs $40$ minutes to empty the pool. Time taken by pipe A to empty the pool, in hours, is

Ajit is ranked seventh from the top and twenty fifth from the bottom in a class. How many students are there in that class?

Taps A and C can fill a tank in $5$ and $20$ hrs respectively. Taps B and D can drain a full tank in $10$and $40$hrs. respectively. If A, B, C and D are opened in a gap of $2$ hrs. in that order the tank gets full in______.

It takes $10 minutes$ for pipe $A$ to fill the tank completely and it takes $40 minutes$ for pipe $B$ to fill the tank completely. If both the inlets are opened together, then how much time will be taken to fill the tank completely

It takes $20 minutes$ for pipe $A$ to fill the tank completely and it takes $30 minutes$ for pipe $B$ to fill the tank completely. If both the inlets are opened together, then how much time will be taken to fill the tank completely

Tap P can fill a cistern in $6 \mathrm{hours}$ and Tab Q can empty the full cistern in $10 \mathrm{hours}$. If both pipes P and Q are kept open simultaneously, then in how many hours will the empty cistern be completely full?

Nine red pipes and twelve blue pipes provide water to a swimming pool. A red pipe can fill the pool in $36$hours whereas a blue pipe can fill it in $48$hours. There was some problem with the water supply and some of the pipes did not supply water at all. As a result it took $50\%$ more time to fill the swimming pool. What could be the number of pipes that stopped working?

Pipe A can fill a tank in $36 \mathrm{minutes}$ and Pipe B can empty the tank in $45 \mathrm{minutes}$. If both the pipes are opened simultaneously, then find the time (in $\mathrm{hours}$) to fill the tank to half its capacity.

Nine red pipes and twelve blue pipes provide water to a swimming pool. A red pipe can fill the pool in $36$ hours whereas a blue pipe can fill it in $48$ hours. There was some problem with the water supply and some of the pipes did not supply water at all. As a result it took $50\%$ more time to fill the swimming pool. What could be the number of pipes that stopped working?

Pipes$\mathrm{A}$ and $\mathrm{B}$ attached to a water tank can fill it in $\text{'}\mathrm{n}\text{'}$ and $\left(\mathrm{n}+6\right)$ hours respectively. Another pipe, $\mathrm{C}$ attached to the same tank can empty the completely filled tank in $\left(\mathrm{n}-3\right)$ hours. If all three of them can completely fill the empty tank in $\text{'}3 \mathrm{n}\text{'}$ hours, then find the time taken by Pipe $\mathrm{C}$ alone to empty the completely filled tank.

A tank can be filled by one inlet pipe in $6 \mathrm{hrs}$ and by another in $8 \mathrm{hrs}$. How long will it take to fill if both pipes are opened simultaneously?

Two pipes A and B, Pipe A can fill the tank in $250 \min$, it is operational for $50 \min$, Pipe B is also opened along with pipe B and fill the remaining tank in $150 \min$. Find the time taken by pipe B alone to fill the tank.

Pipe A can fill a tank in $36 \mathrm{minutes}$ and Pipe B can empty the tank in $45 \mathrm{minutes}$. If both the pipes are opened simultaneously, then find the time (in $\mathrm{hours}$) to fill the tank to half its capacity.

A pipe can fill a tank in $56 \mathrm{hours}$, but it takes $16 \mathrm{hours}$ more due to a leak in its bottam.In how much time ( in $\mathrm{hours}$) can the leak alone empty $83\frac{1}{3}\%$ of the tank?

An inlet pipe can fill an empty tank in $2 \mathrm{hours}$ and an outlet pipe can empty the full tank in $3 \mathrm{hours}$.In what time will the empty tank get filled,if the inlet and th outlet pipes are opened together?

Pipe A can completely fill an empty tank in $11 \mathrm{hours}$. Pipe B can empty the same completely filled tank in $15 \mathrm{hours}$. If they are opened together, in how much time the empty tank will get filled?

Pipe P can fill a tank alone in $7 \mathrm{hours}$. Pipe Q can fill the same tank alone in $13 \mathrm{hours}$. In how much time can they together fill the tank?

Pipe D1 can fill an empty tank in $80 \min$ and Pipe D2 can empty the same tank in $100 \min$. If pipes are opened simultaneously, then in how much time the tank gets completely filled?

Pipes $A$, $B$ and $C$ can fill a tank in $15, 30$ and $40 \mathrm{hours}$, respectively. Pipes $A, B$ and $C$ are opened at $6 \mathrm{A}.\mathrm{M}., 8 \mathrm{A}.\mathrm{M}.,$ and $10 \mathrm{A}.\mathrm{M}.,$ respectively, on the same day. When will the tank be full?

Pipe A and B can empty a full tank in $18 \mathrm{hours} \mathrm{and} 24 \mathrm{hours}$, respectively. Pipe C alone can fill the tank in $36 \mathrm{hours}$. If the tank is $\frac{5}{6}$ full and all the three pipes are opened together, then in how many hours will the tank be emptied?