Donut Pricing
A gourmet doughnut shop charges by topology, so a tiny doughnut costs the same as a big one, while a huge solid 'doughnut hole' is cheaper.
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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/2017-11-24-donut-pricing/ (CC BY-NC 4.0)Transcript
Customer: "Hey! You charged me $2 for this mini doughnut! That's the same price as a regular-sized one!"
Baker: "Price is a topological invariant, obviously. Order smarter next time."
[Another customer happily carries a giant ball labeled "Donut Hole $1"]