To calculate the circumference of a circle, multiply the diameter of the circle in question by pi. You need to know the diameter of the circle to complete this task. More »

To find the arc of a circle, divide the angle subtended at the center of the arc by 360 degrees, then multiply the answer by the circumference of the circle. You need to know the value of pi and must have a protractor to... More »

Find the area of a circle using the equation A=?r^2. The area is equal to the radius, which is the distance from the center of the circle to its edge, times itself, times pi (approximately 3.1415). More »

To calculate a circle's diameter from its circumference, one should divide the circumference by the constant pi, which is an irrational number approximately equal to 3.14159265358979. More »

If the circumference or the area of a circle is known, pi can be used to find the diameter and the radius of that circle. Likewise, if the radius or diameter is known, pi can be used to find out the circumference or the ... More »

The circumference of a circle is the distance around the outskirts of the circle. Knowing the radius of any circle allows one to calculate its circumference. More »

Find the circumference of a circle using the formula 2 x π x r. You need the value of π, or pi, and the radius of the circle. More »

www.reference.com Math Geometry Shapes