It is another name for the perimeter of a circle. The circumference of a circle is calculated using the formula: \(\text{circumference} = \pi \times \text{diameter}\) This number is Pi.

The formula to calculate the area of a circle, with radius \(r\) is: \(\text{area of a circle} = \pi r^2\) ...

THIS book treats of the difficult problem of girders forming a circular arc in plan such as are often used to support the balcony of a theatre. The principles on which the general problem may be ...