Math Puzzle for July 4, 2025

Velga watches as Eva carves a prize-winning duck out of soap

Alameda Post - a regular enneagon that has nine equal sides and nine equal angles which is inscribed by an outer circle and that inscribes an inner circle

A regular enneagon has nine equal sides and nine equal angles.
The enneagon above is inscribed by an outer circle and it inscribes an inner circle.
The difference in the areas of the outer and inner circles is 882.3593285445 m².

Find the area A of the regular enneagon or nonagon as depicted and described.

Send the correct answer to [email protected] for a chance to win a Tucker’s ice cream gift card.

Last week’s winner was John Lovato with A = 1776 square units.

Jeff Smith is a former Math teacher and a retired US Navy Lieutenant Commander. Reach him at [email protected].

Copied!

KQED Curated Content
Thanks for reading the

Nonprofit news isn’t free.

Will you take a moment to support Alameda’s only local news source?