Pi Day with MoMath

Sun Mar 14, 2021
Various times
All ages
$15 and up
National Museum of Mathematics Online

NYC's MoMath celebrates the wonders of Pi with live streams throughout the day.

11am ET (New York): Start your morning off right with some eye-opening pi…
“Roping Around the World”
Test your intuition with a mathematical problem about a rope tied around the Earth. Explore the counterintuitive solution with an engaging, hands-on activity.

11:30am ET (New York): “Why don’t we celebrate Phi Day?”
Phi, also known as the Golden Ratio, is one of the most unique irrational numbers in all of mathematics. Learn about this fascinating number that shows up in all sorts of unexpected places, including a number of MoMath exhibits. Then, discover how the number pi, in contrast, truly is more special and deserving of its own holiday and how pi transcends the basic rules of arithmetic.

2pm ET (New York): Who needs high tea when you can have pi glee?
“Probably Pi?”
While it is impossible to write pi in its entirety, various methods exist to generate better and better approximations. In this crowd-sourced experiment, participants see how the law of large numbers lets us confidently approach pi by using probability. By randomly dropping a needle onto a set of lines, we can converge on pi experimentally, without the need for direct measurement. Help generate data to see how many digits of pi we can get — the more, the mathier!

2:30pm ET (New York): “What is the value of Pi?”
Throughout history, people have tried to compute the exact value of pi. Ancient Babylonians believed that pi = 25/8, Egyptians thought that pi = (16/9)^2 = 256/81, while the Indiana state legislature almost passed a bill in 1897 stating that pi = 3.2. We know now that pi cannot be computed exactly; use geometric constructions to find rational approximations.

7pm ET (New York): Pi by night: BYOP…join Alex Kontorovich for an evening exploration — and bring your own (pizza) pi!


The following materials may be helpful but are not required:

  • a toilet paper or paper towel roll
  • a sharpie
  • an assortment of round household containers
  • a pizza pie

National Museum of Mathematics Online
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