DELHI POLICE MATHS QUIZ

A cistern has 3 pipes $A, B$ and $C . A$ and $B$ can fill it in $3 \mathrm{hr}$ and $4 \mathrm{hr}$ respectively and $\mathrm{C}$ can empty it in 1 hour. If the pipes are opened at 3 pm, 4 pm and 5 pm respectively on the same day, the cistern will be empty at

A tank can be filled by pipe $A$ in 2 hours and pipe $\mathrm{B}$ in 6 hours. At 10 a.m pipe A was opened. At what time will the tank be filled if pipe B is opened at 11 a.m?

Two pipes $A$ and $B$ can fill a cistern in 3 hours and 5 hours respectively. Pipe $C$ can empty in 2 hours. If all the three pipes are open, in how many hours the cistern will be full?

Three taps A, B and C can fill a tank in 50,60 and 30 hours respectively. How long (in hours) would the three taps take to fill the tank if all of them are together?

There are two inlet pipes $\mathrm{A}$ and $\mathrm{B}$ can fill a tank in 20 minutes and 30 minutes respectively. Outlet pipe C can empty the whole tank in 15 minutes. What time will they take (in minutes) to fill the whole tank, if they start together?

Aman, Shubham and vikash can fill a tank in 20 days, 30 days and 15 days respectvely. In how many days Shubham and vikash together can fill the whole tank?

There are two tanks P and Q to fill up a water tank. The tank can be filled in 30 minutes , if both taps are on. The same tank can be filled in 50 minutes , if only tap P is on. How much time will tap Q alone , take to fill up the same tank?

Pipes A and B can fill a tank in 10 hours and 13$\frac{1}{3}$ hours, respectively. Pipe C is an emptying pipe. When all the three pipes are opened together, the tank is filled in 8 hours. In how many hours will Pipe C alone empty 25% of the tank?

Pipes A and B can empty a tank in 15 hours and 18 hours, respectively. Pipe C alone can fill the tank in 6 hours. If all the three pipes are opened together, then two-third part of the tank will be full after:

Pipes A and B can together fill a tank in 20 hours and pipe C can empty $40 \%$ of the tank in 20 hours. Find the time taken by all the 3 pipes together to fill $60 \%$ of the tank.