On Monday afternoons, I host a math circle for elementary school kids on Bainbridge Island, WA, where my family and I live.  The pictures above are from our practice on my birthday this year.

Team coach Anne Willhoit baked me a round cake and adorned it with a math problem to solve. There was a chord, length “k” drawn in frosting across the top, and a perpendicular line of length “p” bisecting it.

The card on the cake read: GIVEN k and p, find an expression for the radius of the circle.

Before eating the cake, our mathletes collaborated on how to solve the problem.  They identified the Pythagorean triangle and we were on our way to the solution.

 

Thank you to Anne and Ryan Willhoit, for the delicious treat!