In big cities such as Delhi, milk is sold at milk booths. At these booths, there is always a queue for buying milk in the morning and in the evening. People stand in a queue and one by one they move on to the window. Each person pays the money for the milk according to requirement. He gets special counters. Then he moves on to the machine with a slot to insert the counter. Only one counter can be inserted at a time into the slot. Then half a liter of milk is poured into the vessel. People are in a hurry to get to the window or the machine. Sometimes, some people try to break the queue. This leads to small arguments and quarrels. Some wise persons in the queue are able to stop these quarrels.