Three lawyers and three MBA's are traveling by train
to a conference.
At the station, the three lawyers buy tickets and
watch as the three MBA's buy only a single ticket.

"How are three people going to travel on only one
ticket?" asks a lawyer.
"Watch and you'll see," answers an MBA.

They all board the train. The lawyers take their
respective seats but all three MBA's cram into a
restroom and close the door behind them.
Shortly after the train has departed, 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 lawyer saw this and agreed it was quite a clever
idea. So after the conference, the lawyers decide to
copy the MBA's on the return trip and save some money.

When they get to the station, they buy a single
ticket for the return trip.
To their astonishment, the MBA's don't buy a ticket at
all.

"How are you going to travel without a ticket?" says
one perplexed lawyer.
"Watch and you'll see," answers an MBA.
When they board the train the three lawyers cram into
a restroom and the three MBA's cram into another one
nearby. The train departs.

Shortly afterward, one of the MBA's leaves his
restroom and walks over to the restroom where the
lawyers are hiding. He knocks on the door and says, 
"Ticket, please."