Stairs

Bill, Jim, and Scott were at a convention together and were     sharing a large suite on the top of a 75 story sky scraper.     After a long day of meetings they were shocked to hear that the     elevators in their hotel were broken and they would have to climb     75 flights of stairs to get to their room.  Bill said to Jim and     Scott, let's break the monotony of this unpleasant task by     concentrating on something interesting.  I'll tell jokes for 25     flights, and Jim can sing songs for 25 flights, and Scott can     tell sad stories the rest of the way.  At the 26th floor Bill     stopped telling jokes and Jim began to sing.  At the 51st floor     Jim stopped singing and Scott began to tell sad stories.  "I will     tell my saddest story first," he said.  "I left the room key in     the car!"