Philosophy of Mathspeaking topic
A rope wraps snugly around the Earth's equator. Lengthen it by just one meter and lift it evenly all the way around, and it rises about 16 centimeters off the ground, enough for a cat to walk under. How can one meter matter this much on a circle the size of a planet?
— circle geometry, the rope around the Earth puzzle
practice with this topic
Set the timer (5-30 min), take 20 seconds of prep if you like, start talking. Jot your thoughts onto the sticky-note board.
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