So the story goes that a student had been given this problem, had
solved it the hard way (infinite series), found the easy solution
(that you've just given) and was trying it out on lots of people.
He met von Neumann at a party and posed it to him, whereupon he
(von Neumann) thought for a moment, and then gave the right answer.
The student was disappointed, and said "You'd be surprised just how
many people try to sum the infinite series." Von Neumann looked
puzzled and said: "Is there another way?"
