The **Functions of Numbers chart** [Figure 1-10] is included in this chapter for convenience in making computations. Each column in the chart is listed below, with new concepts explained.

- Number, (N)
- N squared, (N2)
- N cubed, (N3)
- Square root of N, (√N)
- Cube root of N, ( 3√N)
- Circumference of a circle with diameter = N. Circumference is the linear measurement of the distance around a circle. The circumference is calculated by multiplying the diameter of the circle by 3.1416 (3.1416 is the number referred to as pi, which has the symbol π). If the diameter of a circle is 10 inches, then the circumference would be 31.416 inches because 10 × 3.1416 = 31.4160.
- Area of a circle with diameter = N. Area of a circle is the number of square units of measurement contained in the circle with a diameter of N. The area of a circle equals π multiplied by the radius squared. This is calculated by the formula: A = π × r2. Remember that the radius is equal to one-half of the diameter. Example: A cockpit instrument gauge has a round face that is 3 inches in diameter. What is the area of the face of the gauge? From Figure 1-10 for N = 3, the answer is 7.0686 square inches. This is calculated by: If the diameter of the gauge is 3 inches, then the radius = D⁄2 = 3⁄2 = 1.5 inches. Area = π × r2 = 3.1416 × 1.52 = 3.1416 × 2.25 = 7.0686 square inches.

ASA – AMT General, Airframe and Powerplant Prepware for 2017. Get ready for your FAA AMT Knowledge Exams with the most trusted source in aviation training. Includes the contents of the Computer Testing Supplement, with the same FAA legends, figures, and charts you’ll be issued at the testing center before you take your official test.