It depends on the information you have. If you remember the formulas for area and circumference, you can plug in what information you know in order to solve for the information you don't.
You can multiply the radius by 2.
If you are given the area, divide by pi (3.14) and then take the square root and multiply by 2.
If you are given the circumference, divide by pi (3.14).
The DIAMETER of a circle is any point on the circle to another point, straight across.
The RADIUS of a circle is like the diameter, only from any point, to the very middle.
To find AREA: multiply circumference by pi.
To find Diameter, multiply the radius by two.
to find radius: divide diameter by 2.
using the formula circumference=diameter X pi: circumference=diameter X pi circumference/pi=diamter X pi/pi circumference/pi=diameter therefore, diameter=circumference/pi diameter=12mm/3.14 diameter=3.821mm
To find area of a circle using diameter, you use this formuler. Area=pi(diameter/2)(diameter/2)
Circumference = Pi * diameter
The circumference of a 7-foot diameter circle using 3.14 for Pi is: 21.98 feet (diameter x Pi = circumference).
the importance of pi is when u do have the diameter of a circle and u have the radius you can find the diameter of the circle and the circumference
If: circumference = pi*diameter Then: pi = circumference/diameter
Diameter = circle's circumference/pi
circumference of a circle = pi*diameter or 2*pi*radius
pi times diameter
Diameter = circumference/pi
Pi x diameter
multiply the diameter times pi (3.14159265)
Multiply the diameter by the constant pi.
Since circumference is found by multiplying pi by the diameter of the circle, the diameter can by found using the inverse operation. diameter = circumference/pi
Pi is the number of times the diameter of a circle will fit into the circumference. Pi is not a circle, and does not have a circumference or area. To calculate a circumference USING pi, the circumference is diameter * pi. To find the area using pi, area = pi * radius * radius
circ = 2 pi r = pi d
EDIT: To find the diameter, using the circumference - you divide the circumference by the value of Pi - Snakester1962 (Supervisor)