"What a bunch of idiots" the mathematicians said. "When the ticket master comes through, they'll be kicked off the train!"
Sure enough, on board the train, they could hear the ticket master in the next car, saying "Tickets please".
The three engineers ran into the train bathroom and closed the door. The ticket master came in and knocked on the door and said "Tickets please".
They slipped the ticket under the door and the ticket master moved on.
"That's brilliant!" The mathematicians exclaimed. "We should do that on our way home!"
After the conference ended and they were traveling home the mathematicians all bought one ticket to share between them... and the engineers didn't buy ANY ticket at all!
"What a bunch of idiots" the mathematicians said. "What are they going to do when the ticket master comes through? They'll be kicked off the train".
On the train they soon heard the ticket master in the next car saying "Tickets please".
All three mathematicians ran into one bathroom and closed the door. All three engineers ran into the other bathroom and closed the door. As soon as both doors were closed, an engineer came out of the bathroom and knocked on the mathematician's door and said
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