Calculating π by hand

For Pi Day 2016 I tried to calculate π by hand, using an infinite series. It goes ok. Before you even start: - Yes, I know π Day requites writing the date MM/DD. By objective measures: the wrong way. I don't care. My love of π is stronger. - My opinion of Tau is a matter of public record: http://youtu.be/ZPv1UV0rD8U CORRECTIONS: - At 17:23 it should be π/4 not 1/π. That was contamination from the next graphic. (First spotted by Najeeb Sheikh and Jake Trookman.) Check out y-cruncher: http://www.numberworld.org/y-cruncher/internals/formulas.html Calculating pi by weighing a circle: https://www.youtube.com/watch?v=Ngj0a57Rlb0 Calculating pi with a pendulum: https://www.youtube.com/watch?v=qYAdXm69l8g Music by Howard Carter Design by Simon Wright MATT PARKER: Stand-up Mathematician Website: http://standupmaths.com/ New book: http://makeanddo4D.com/ Nerdy maths toys: http://mathsgear.co.uk/