Written below: d equals C divided by pi., The circumference of a circle is given by the formula 𝑪 = π𝒅. The diameter has been multiplied by π to give the circumference.

I am Pi, the ratio of the circumference of a circle to its diameter. Picking up the phone here at the Smithsonian, I set out to find out more about Pi and how it is represented in the national ...

To do this, start by cutting a 3-inch piece of string to serve as the radius of the circle. What’s the radius? It’s half the diameter. Okay, but what’s the diameter?

It is derived simply, by dividing the circumference of a circle by its diameter, or π = C/d, but the result is a never-ending "irrational" number: 3.14159265.

Approximating Pi By Rick Groleau Posted 09.01.03 NOVA Around 250 B.C., the Greek mathematician Archimedes calculated the ratio of a circle's circumference to its diameter. A precise determination ...

The constant π is traditionally defined as the ratio of a circle's circumference to its diameter. As I pointed out in the first installment of this series, the fact that this is well-defined (i.e ...

It’s hard to pinpoint who, exactly, first became conscious of the constant ratio between the circumference of a circle and its diameter, though human civilizations seem to have been aware of it ...