In the high school gym, all the girls in the class were lined up against one wall, and all the boys against the opposite wall. Then, every ten seconds, they walked toward each other until they were half the previous distance apart. A mathematician, a physicist, and an engineer were asked, "When will the girls and boys meet?"

The mathematician said: "Never."

The physicist said: "In an infinite amount of time."

The engineer said: "Well... in about two minutes, they'll be close enough for all practical purposes."

A mathematician, a physicist and an engineer are each given $50 to measure the height of a building.

The mathematician buys a ruler and a sextant, and by determining the angle subtended by the building a certain distance away from the base, he establishes the height of the building.

The physicist buys a heavy ball and a stopwatch, climbs to the top of the building and drops the ball. By measuring the time it takes to hit the bottom, he establishes the height of the building.

The engineer puts $40 into his pocket. By slipping the doorman the other ten, he establishes the height of the building.