Today we investigated perfect shuffles and made several models for them. We had 22 participants. Many thanks to Fairfield High School and Carlo in particular for hosting our circle.

This document outlines some of the approaches we took to the topic and mentions connections to additional mathematical topics.

Here's few comments on powers of 10 modulo n and repeating decimals for the fraction 1/n

And here's a proposal for describing perfect shuffles of n cards in terms of powers of 2 modulo n-1.

## 8 March 2014

## Fairfield High School

Today we investigated perfect shuffles and made several models for them. We had 22 participants. Many thanks to Fairfield High School and Carlo in particular for hosting our circle.

This document outlines some of the approaches we took to the topic and mentions connections to additional mathematical topics.

Here's few comments on powers of 10 modulo n and repeating decimals for the fraction 1/n

And here's a proposal for describing perfect shuffles of n cards in terms of powers of 2 modulo n-1.