Band around the Earth Puzzle
The circumference of the Earth is approximately 40,000 kilometers, and someone has just made a metal band that circles the Earth, touching the ground at all locations.
You come along at night, as a practical joke, and add just 10 meters to its length (one hundredth of one kilometer !)
It is now one four-millionth longer, and sits magically just above the ground at all locations
How far has it risen ... could a flea, a rabbit or even a man squeeze underneath it?
Do you have the answer? Check against our solution!