3455 School St

Lafayette, CA 94549

USA

**Facilitator**: **Marc Roth** — Currently a math teacher at Main Street Scholars in Half Moon Bay, veteran MTC and conference speaker, and retired after 43 years as a public school secondary math teacher. BA in mathematics from UC Berkeley.

**Topic**: **Niceties of the Harmonic Mean** — The harmonic mean is a very interesting but largely neglected topic. It can enrich the pre-algebra, algebra, and geometry curriculum. We will first discover a little-known method of how to locate the harmonic mean of two numbers on the number line by looking at it as a special weighted average. This will lead to valuable worksheets that provide multi-step fraction practice but can also lead students to discover an interesting pattern. We will then extend the analysis and introduce further worksheets. If time permits, we will also look at the connection to Pythagorean triangles, which are right triangles, each of which has three sides of integer length. The best example is the 3-4-5 right triangle. This topic will be supported with original geometry tiles.

If you plan to attend, **RSVP** here.