You will need

- You will need the following values:
- R - length of radius of the circle;
- D - the length of the diameter of a circle;
- π is a constant (π = 3.14)

Instruction

1

Method 1. Let the plane of a circle. Its radius is equal to R. Then

L = 2nr.

Example: the Radius

**the length**L of this**circle**is considered thus:L = 2nr.

Example: the Radius

**of the circle**R = 5 cm Then the length of**circumference**L = 2*3.14*5 = 31.4 cm2

Method 2. Given a circle with diameter D. Then L is:

L = πD.

Example: the Diameter

L = 3.14*10=31.4 cm

L = πD.

Example: the Diameter

**of a circle**D = 10 cm Then L is calculated as:L = 3.14*10=31.4 cm

Note

The answers in the first and second method are equal, because the length of the radius equal to half the length of the diameter of the circle.