Challenge: Do a Mathemagical Performance

One of the members of the Natural Math group pointed us to a BBC article, "Taking Maths to the Street." The author of the article (who isn't big on math) and a bunch of math teachers and students get trained to do math tricks and then go out on the street, trying to entice people to watch them. She called it 'busking.' I think that includes putting a hat out for donations, but she didn't mention that part. I was disappointed that the author didn't manage to do her trick properly. Is her article perpetuating the myth that math(s) is too hard for 'regular people' to get?

My math poem challenge back in January was a hit, so let's try it again. This time the challenge is to do some street performing using math. I think it's a great way to show the world that math can be fun. Should we have a way to determine a winner? Should it be the one who gets the most money in their hat?¹

You might want to do this with a few friends. Having a group of you, like they did in the article, might make it easier to attract attention. And maybe it would be a good idea to wear some cool math shirts. I'd like mine to say mathemagician. I wonder if I could find something like that... Yes...

I'd love some discussion here about other tricks that would work well for this. The article mentions two: The first, determining the day of the month of someone's birthday by which of five cards they say it shows up on, is based on binary. The other trick is a variant of Nim - each player takes from one to three post-its off the assistant on their turns, and the post-it with the $20 bill attached must be the last one taken off.

The article's author used 8 post-its. I think this trick would be more mysterious if you started with more. I'd recommend asking the volunteer whether they want to go first or second while you're putting the post-its on your assistant. If they want to go first, you could put on 16 (or any multiple of 4). If they want you to go first, you could put on 17 to 19 (or anything not a multiple of 4).

I could probably go over to SF and try this by the Powell Street Cable Car stop; there's usually a long line there. If I can find some else willing to be a fool for math² with me, I promise to do it at least once. (Is anyone reading this from the Bay Area?)

Who else is game? Step right up! Getcher number here!



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¹Contest ends at the end of summer, September 20.
²I wrote this full of enthusiasm yesterday morning. Now I'm a little nervous. But hey, it's a small commitment, and if it bombs, I don't have to do it again, right?