This puzzle is rated 2-stars (medium).
Lets image the equator of the Earth to be 40,000 kilometers long (in actual fact it is 40,075.16 kilometers!) and that the surface of the equator is perfectly flat.
I take a 40,000 kilometre piece of rope and tightly wrap it around the equator. There are no gaps and the two ends of the rope meet perfectly.
However, I don't want the rope to be tightly wrapped around the equator but be lifted 1 metre above the surface of the equator all the way around.
Clearly I will need more rope... how much extra rope will I need?
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