Pi, a mathematical constant denoted by the Greek letter π, is the ratio of a circle's circumference C to its diameter d: π = ...

Swiss researchers said on Monday they had calculated the mathematical constant pi to a new world-record level of exactitude. The constant π is represented in this mosaic outside the Mathematics ...

March 14 is Pi Day, a chance for people around the world to celebrate everyone's favorite mathematical constant "π" (pronounced like the word "pie.") Pi is an incredibly important number in many ...

Imagine a cup of tea. Wrap a piece of string around the circumference of the cup, and measure the length of the string. Then, lay your spoon on top of the cup, making sure it lies across the center of ...