Saw this neat geometry problem shared by Tina Cardone on Twitter earlier today:
One little spoiler in the first video below just in case you want to think through the problem first.
There are a couple of algebraic solutions to the problem that aren’t too difficult. The result is so cool and so simple, though, that I thought there must be a nice geometric solution, too. It took me a while to see it, but eventually I stumbled on the right idea. It made for a fun Sunday afternoon 3D printing project.
Here’s the first part:
and the second part. Spoiler warning again, though the warning this time is that I don’t give the full solution. Showing why the last two shapes have the same area is the fun part of seeing the geometric solution to this problem 🙂
Mike's Math Page 
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