Evan O’Dorney leaps from his seat and snatches the chalk from his teacher’s hand. “I think it goes like this,” the eighth-grader exclaims. He has come up with a formula for the number of ways to ...

I had never heard the term, “math circle,” until a few weeks ago when I stumbled across an article in The Atlantic about the growing number of American kids excelling in the highest levels of math. It ...

Divide the circumference of a baseball by its diameter and you get 3.14. Divide the circumference of Earth by its diameter and you get 3.14. Divide the circumference of a pizza, coin or, well, pie and ...

Arc length is a fraction of circumference. Area of a sector is a fractions of the area of a circle. Both can be calculated using the angle at the centre and the diameter or radius. Practice circle ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

Jeff Smith's Math Puzzle for June 5, 2026 – Trapezoid traps circle, Euclid pays ransom. The post Math Puzzle for June 5, 2026 ...