 Hello and welcome to the session. I am Deepika here. Let's discuss a question which says if armand connects a pipe of internal diameter 20 centimeter from a canal into a cylindrical tank in her field which is 10 meter in diameter and 2 meter deep. If water flows through the pipe at the rate of 3 kilometer per hour in how much time will the tank be filled? Now we know that speed is equal to distance upon time or time is equal to distance upon speed. Again volume of a cylinder is equal to pi r square h where r is the radius of the base of the cylinder and h is the height of the cylinder. So this is a key idea behind our question. We will take the help of this key idea to solve the above question. So let's start the solution. Now according to the question if formal connects a pipe of internal diameter 20 centimeter from a canal into a cylindrical tank in her field. So we are given the internal diameter of the connecting pipe. So the internal diameter of the connecting pipe equal to 20 centimeter and this is equal to 20 upon 100 meter because 1 meter is equal to 100 centimeter and this is again equal to 1 over 5 meter. Therefore radius of the connecting pipe is equal to 1 upon 5 into 2 meter which is equal to 1 over 10 meter. Now the water flows through the pipe at the rate of 3 kilometer per hour that is in 60 minutes the water flows equal to 3 kilometer which is equal to 3000 meter. Therefore in one minute the water flows is equal to 3000 meter upon 60 which is equal to 50 meter. Therefore volume of water one minute through the pipe which is cylindrical is given by the formula pi r square h and this is equal to let us take pi is 22 upon 7 into r square and radius is 1 by 10 meter to 1 by 10 into 1 by 10 into now height is 50 meter because it is the length of water which flows in one minute diameter of the cylindrical tank. Therefore radius of the cylindrical tank is equal to 5 meter. Now depth of the cylindrical tank is given to us 2 meter. Therefore volume of cylindrical tank is given by the formula pi r square h take pi is 22 upon 7 into 5 into 5 into 2 meter cube. Let the tank is filled in x minutes. Therefore volume of water that flows in x minutes equal to volume of the cylindrical tank the volume of water flowing in one minute through the pipe is 22 upon 7 into 1 by 10 into 1 by 10 into 50 meter cube. Therefore the volume of water that flows in x minutes is 22 upon 7 into 1 by 10 into 1 by 10 into 50 into x is equal to volume of cylindrical tank which is 22 upon 7 into 5 into 2. Now we will solve this equation we can cancel 22 upon 7 on both the sides. So this implies x is equal to x is equal to 100 minutes. Therefore it will take 100 minutes fill the cylindrical tank. Hence the answer for the above question is 100 minutes. I hope the solution is clear to you. Bye and take care.