Math on R15Cookie Noteshttps://r15cookie.com/tags/math/Recent content in Math on R15Cookie NotesHugoen-usSteve Miller [BY-NC 4.0](http://creativecommons.org/licenses/by-nc/4.0/)Mathhttps://r15cookie.com/info/math/Mon, 01 Jan 0001 00:00:00 +0000https://r15cookie.com/info/math/ Approximate Pi Day — July 22nd as 22/7. Site Source International Slide Rule Museum — 7,000+ images of slide rules. Also includes simulators