Three engineers and threeaccountants are traveling by train to a conference. At the station, the three accountantseach buy tickets and watch as the three engineers buy only a single ticket."How are three people going to travel on only one ticket?" asks an accountant. "Watch and youll see,"answers an engineer. They all board the train. The accountants take their respective seatsbut all three engineers cram into a restroom and close the door behind them.Shortly after the train hasdeparted, the conductor comes around collecting tickets. He knocks on the restroom doorand says, "Ticket, please." The door opens just a crack and a single arm emergeswith a ticket in hand. The conductor takes it and moves on.The accountants saw this and agreed it was quite a clever idea. So after the conference, the accountants decide to copy theengineers on the return trip and save some money (being clever with money, and all). Whenthey get to the station they buy a single ticket for the return trip.To their astonishment, the engineersdont buy a ticket at all. "How are you going to travel without a ticket?" saysone perplexed accountant. "Watch and youll see," answers an engineer. When theyboard the train the three accountants cram into a restroom and the three engineers craminto another one nearby. The train departs.Shortly afterward, one of theengineers leaves his restroom and walks over to the restroom where the accountants arehiding. He knocks on the door and says, "Ticket, please."