2019 Festival: How Many Degrees are in a Martian Circle? (10:15am showing) | National Math Festival
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2019 Festival: How Many Degrees are in a Martian Circle? (10:15am showing)

Saturday May 4, 2019 from 10:15am - 11:00am ET

Who chose the number 360 for the count of degrees in a circle? Why that number? And why do mathematicians prefer not to use that number for mathematics? Why is the chosen direction of motion in mathematics counterclockwise when the rest of world naturally chooses clockwise? Why are fingers and single digit numbers both called digits? Why do we humans like the numbers 10, 12, 20, and 60 particularly so? Why are logarithms so confusing? And why is base e the “natural” logarithm to use? What happened to the beautiful vinculum? (Bring back the vinculum, I say!) Why did human circle-ometry become trigonometry? Let’s spend a session together exploring tidbits from the human—and nonhuman—story and development of mathematics.

This presentation will be repeated from 2:00-2:45pm.

Room 201, Level 2, Walter E. Washington Convention Center

Age Level



Dr. James Tanton

James Tanton (PhD, Princeton 1994, mathematics) writes books and video courses, advises on curriculum, consults with teachers, and gives demonstration classes and professional development sessions across the globe. He has taught mathematics both at university and high-school institutions and is absolutely committed to promoting effective and joyful mathematics thinking,... Learn more