2

2

Area = 0.7854 (D - d ). or 0.7854 (D - d) (D + d)

Example: D = 10", d = 3"

2

2

Area = 0.7854 (10 - 3 ) = 71.4714 sq. in.

2

2

Area = 0.2146 R = 0.1073 C

Example: R = 3 2

Area = 0.2146 X 3 = 1.9314

Area may be found as follows:

Divide the figure into equal spaces

as shown by the lines in the figure.

(1) Add lengths of dotted lines.

(2) Divide sum by number of spaces.

(3) Multiply result by A.

have a value of 198. This value is now multiplied by

l/2, resulting in a product of 99. Since all values are in

inches, the area is 99 square inches.

A surface has two dimensions--length and width.

It is bounded by lines that are either straight or curved.

14-22