Written below: C equals two pi r., The formula for the circumference of a circle uses either the diameter or the radius of the circle. End of image gallery Question ...

The radius can be used to calculate a circle's diameter, area and circumference. ... you can construct a formula in Microsoft Excel to do the math for you. ... As an example, ...

Everybody knows the value of pi is 3.14…er, something, but how many people know where the ratio came from? Actually, the ratio came from nature—it’s the ratio between the circumference of a ...

For example, the Indian scholar Madhava, who lived from 1350 to 1425, found that pi equals 4 multiplied by a series that begins with 1 and then alternately subtracts or adds fractions in which 1 ...

Known around the world as "Pi Day," it’s a time to celebrate one of mathematics' most famous constants: Pi, the ratio of a circle's circumference to its diameter, approximately 3.1415.

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 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.

The circumference of Earth barely changes after 16 digits of pi. (Image credit: Shutterstock) Take our planet: Earth has a diameter of around 7,900 miles (12,700 kilometers), which means its ...

Learn about the definition of pi in relation to a circle with this BBC Bitesize Maths article. For students between the ages of 11 and 14.