# Reference Material

- To find the circumference of a circle, multiply diameter by 3.1416.
- To find diameter of a circle, multiply circumference by .31831
- To find area of a circle, multiply square of a radius by 3.1416.
- To find surface of a sphere, multiply square of diameter by 3.1416
- To find volume of a sphere, multiply cube of diameter by .5236.
- To find side of an inscribed square, multiply diameter by .7071.
- To find side of an equal square, multiply diameter by .8862.
- To find diagonal of a square, multiply side by 1.4142.
- To find diameter of an equal circle, multiply side by 1.128.
- To find area of an ellipse, multiply product of both diameters by .7854.
- To find contents of a cone, multiply area of base by 1/3 altitude.
- To find surface of frustrum of a cone or pyramid, multiply sum of circumferences of both ends by 1/2 slant height and add area of both ends.
- To find contents of frustrum of cone or pyramid, multiply areas of top and bottom and take square root. Add area of top
- 1 cubic foot of water contains 6.23 imperial gallons.