How do you find the area of a circle? Can you measure the area of a circle and use that to find a value for Pi?

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 work out the area of a circle: Find the value of the radius. If the diameter is given, this must be halved. Substitute the value of the radius into the formula for the area of a circle.

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.

He said the crop pattern 'clearly shows' the first ten digits of pi, which - as many will remember from their schooldays - is used to calculate the area of a circle using the formula Pi r squared.

It’s a most auspicious holiday for math lovers. Saturday, March 14, 2015 is Pi Day, a celebration of the irrational number that describes the ratio of a circle’s diameter to its circumference ...

National Pi Day is held each year on March 14. It honors 3.14 the ratio of the circumference of a circle. You can also get deals on food too.