An infinite number of mathematicians walk into a bar. The first one orders a beer. The second orders half a beer. The third, a quarter of a beer. The bartender says "You're all idiots", and pours two beers.
Or its sibling: a genie grants both a mathematician and an engineer their greatest desire to be located at the end of the room given that each step they take towards it is half the distance than their last. The mathematician throws his arms up and yells "Impossible! I'll never reach it," and storms out of the room. The engineer just smiles and says to the genie, "I can get close enough."
An infinite number of mathematicins walk into a bar. The first one orders a beer. The second orders half a beer. The third, a third of a beer. The bartender says, "what do you think I am, an idiot?" and kicks them all out.
An infinite number of mathematicians walk into a bar. The first one orders a beer. The second orders two beers. The third, three beers. The bartender says, "you guys owe me a twelfth of a beer."
more: http://www.metafilter.com/76377/Two-mathematicians-walk-into...