Math with Bad DrawingsCartoon Archive

Pi Halloween

March 10, 2017

A muddled explanation of Pi Day leads a friend to conclude the sun's circumference-to-diameter ratio changes with the date.

Use this cartoon

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/2017-03-10-pi-halloween/ (CC BY-NC 4.0)
Transcript

A: "Why do we celebrate Pi Day on 3/14?"

B: "Because... well, take the sun. Its circumference is roughly 3.14 times its diameter. Hence, March 14!"

A: "Oh, I get it! And on Halloween, the sun's circumference is 10.31 times its diameter!"

B: "Ummm..."

Topics
Number & Arithmetic › PiGeometry › CirclesGeometry › Circumference
Level
Middle SchoolHigh School
Themes
History & HolidaysCommon MistakesNature & Science