Circle
Area=Square of Diameter x 0.7854 or Square of Radius x 3.1416
Circumference= Diameter x 3.1416
Diameter=Circumference x .3183
Doubling diameter increases area four times; tripling diameter increases area nine times, etc...
Area of circular ring = 3.1416 x (outside diameter squared minus inside diameter squared)
Square
Area=square of side
Diagonal=side x 1.4142
Side=diagonal x 0.7071
Rectangle
Area= Length x Width
Diagonal= Square root of sum of squares of width and length
Cube
Area of Surface=square of side x 6
Volume=Cube of side
Diagonal=Side x 1.732
Cylinder
Area of Curved Surface=diameter x length x 3.1416
Volume=square of diameter x length x 0.7854
