Sunburn Theory
Two graphs: in theory, skin tans gradually with sun exposure; in practice it jumps from pasty to burnt.
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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/2018-08-28-sunburn-theory/ (CC BY-NC 4.0)Transcript
[THEORY] Graph of skin color (pasty → tan → burnt) vs. sun exposure: a steady straight line.
[PRACTICE] Same axes: flat at pasty, then a sudden jump straight to burnt.