MCQs and tricks for competition exam.

  Pipe and tank questions are solved in the same way as time and work questions are solved.  Here very short and long method have also been used so that the preparation of your examinations can be done easily.  In L.C.M method, L.C.M is the total capacity of the tank or the total amount of water to be filled .  The following tricks will be used to solve the questions of pipes and tanks:-  A) Pipe A takes y time to fill a tank and Pipe B takes x time to fill that tank.  In how much time will the tank be filled if both are opened together?  T  = {(xy)÷(x+y)}  B) Pipe A takes x time to fill a tank and Pipe B takes y time to empty that tank.  How long will it take to fill the tank if both the pipes are opened simultaneously?  T= {(xy)÷(y-x)}  C) Pipes A and B fill a tank in x and y time respectively.  Pipe C takes z time to empty the tank. If all three are opened together, then how much time will it take to fill the tank? ...