The Elf Theorem
A huge sheet of wrapping paper next to a small book barely gets the book covered, illustrating the joke 'theorem' that you need six times the surface area.
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Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2016-12-23-the-elf-theorem/ (CC BY-NC 4.0)Transcript
[Title] "The Elf Theorem"
"Wrapping Paper Required = 6 × Surface Area"
Person (staring at a wrapped book): "HOW WAS THAT NOT ENOUGH"