pi * d
Area = (pi) (R)2
Area in square units = pi*radius2
Circumference=2*pi*radius
V=Pi*R2*H
To find the circumference of a circle the formula is: 2*pi*radius or diameter*pi
Pi X D = Circumference. To find Diamater if you know Circumference, divide Circumference by Pi (3.14).
The circly bit on the outside
You are thinking of pi.A = (pi)r^2
A=pi times r times r
To find the area of a cylinder a simple formula used is A=2(pi)r2 +2(pi)rh with; R being the radius of the circle and H being the height of the cylinder. the formula can also be translated as; 2(pi)rX[r+h]
The formula of percentage is pi. This is used in math.