Three engineers and three accountants are travelling by train to a conference. At the station, the accountants watch as the engineers buy only a single ticket between them.
“How can 3 people travel on only one ticket?” asks an accountant.
“Just watch,” says an engineer.
They all board the train. The accountants take their seats but all 3 engineers cram into a restroom and close the door behind them. Soon the conductor comes around collecting tickets. He knocks on the restroom door and says, “Ticket, please.” The door opens just a crack and a single arm emerges with a ticket in hand. The conductor takes it and moves on.
The accountants agree this is quite a clever idea, so after the conference, they decide to try it on the return trip. At the station they buy a single ticket, but to their astonishment, the engineers don’t buy a ticket at all.
“How are you going to travel without a ticket?” asks one perplexed accountant. “Just watch,” answers an engineer.
When they board the train the accountants cram into one restroom and the engineers cram into another. The train departs. Shortly afterward, one of the engineers leaves his restroom and walks over to the restroom where the accountants are hiding. He knocks on the door and says, “Ticket, please.”