Selecting at least 2 black balls from a set of 4 black balls in total selection of 3 balls can be 2 black and 1 white balls 3 black and 0 white balls Therefore, our solution expression looks 4C2 × 3C1 + 4C3 × 3C0 6 X 3 + 4 X 1 = 18 + 4 = 22 ways
A tank has three pipes, X, Y, and Z. X can fill the tank in 8 hours, Y can fill it in 12 hours, and Z can empty it in 6 hours. If X, Y, and Z are opened...
Two inlet pipes, each with the same capacity, can fill an empty tank 'A' together in 20 minutes. There is also an outlet pipe that can empty 40% of the ...
Pipe ‘A’ and pipe ‘B’, together can fill 20% of a tank in 6 hours while pipe ‘C’ takes 34 hours to empty it. ...
Tap A can fill a tank in 20 hours and tap B can emptied it is 25 hours. Tap A starts filling and they opened for 1 hour each alternatively in what time...
The difference between total SI earned on Rs 'P' at 18% p.a. for 3 years and total CI earned on same sum at 20% p.a. for 2 years when compounded annuall...
Pipe P can fill a tank in 12 hours, while pipe Q can fill the same tank in 20 hours. Both pipes are initially opened to fill an empty tank, but after 5 ...
Pipe 'A' can fill a water tank in 6 hours, while pipe 'B' requires 8 hours to do the same. When a third pipe, 'C', also contributes, the tank is filled ...
A tank has two inlet pipes and one outlet pipe. Pipe A can fill the tank in 4 hours, and Pipe B can fill it in 6 hours. The outlet pipe C can empty the ...
Two pipes A and B can fill a tank in 15 hours and 25 hours respectively. If both the pipes are opened simultaneously, in how much time the tank will be ...
A water tank has two holes. The 1 hole alone empties the tank in 9 minutes and 2nd hole alone empties the tank in 6 minutes. If water leaks out at a con...
