Double the Radius to Calculate the Diameter.
Circumference = diameter*pi
Circumference of a circle = 2*pi*radius or pi*diameter
You can either measure it, or calculate it if you know the diameter (radius = diameter / 2), or the circumference (radius = circumference / (2pi)).
Using the Circumference And Area.
Radius of a circle = diameter/2
Radius of a circle = diameter/2
Double the Radius to Calculate the Diameter.
Divide the diameter by 2.
Circumference = diameter*pi
Doubling the radius will give the diameter and times this by pi will give the circumference of the circle.
Circumference of a circle = 2*pi*radius or pi*diameter
You can either measure it, or calculate it if you know the diameter (radius = diameter / 2), or the circumference (radius = circumference / (2pi)).
Of a circle: divide the length of the circumference by the value of Pi (about 3.14159). The answer is the diameter. Half of the diameter is the radius
you have to quote the diameter or radius or circumference of the circle to calculate the area. If diameter 78.53. If radius 314.15. If circumference 7.95
Using the Circumference And Area.
If you know the circumference, the ration of the diameter to the circumference is π, so diameter = circumference/π If you have the radius, diameter = 2 x radius