This may be a specific number of decimal places or significant figures. The circumference of a circle is the distance around the shape. The circumference is the perimeter of the circle.

Around 250 B.C., the Greek mathematician Archimedes calculated the ratio of a circle's circumference to its diameter. A precise determination of pi, as we know this ratio today, had long been of ...

WEST PALM BEACH, Fla. (AP) — Math enthusiasts around the world, from college students to rocket scientists, celebrate Pi Day, which is March 14 or 3/14 — the first three digits of an infinite number ...