Accidental Area Problem

Every summer, I participate in math photo challenge on Twitter. This week’s prompt was “area”; we were specifically instructed to “look for shapes made from one or more simple polygons or circles”. I found a very rich example right by the water fountain in the lobby of the San Diego Museum of Art. I was…
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Introducing Mobies!

This story started with our desire to expand the capability of the Geometiles® to make transformable hinged constructions. In particular, we were interested in making flexagons using the equilateral and square Geometiles tiles. Flexagons are polygons typically made of paper, which can be folded to expose certain faces and hide others. They were invented by…
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Lefty or righty? A few words about chirality

Do you see anything unusual about this picture? These two boys are identical twins; but not just any twins: they are mirror twins! That means that many of their features are mirror images of each other. What you can’t see in the picture is that one of the boys is a left-handed and the other…
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