About Perimeter Of A Circle Formula
The perimeter of a circle can be calculated using the perimeter of a circle formula. A circle's perimeter is its boundary or the entire arc length of the circle's periphery. The circumference of a circle is the term used to describe its perimeter. As a result, the circle's perimeter shows us how big a circle is, hence it's also known as the circumference of a circle formula. Let's look at the perimeter of the circle formula in more detail, using examples.
What is the perimeter of a circle formula?
The formula for the perimeter of a circle contains three parts: two constants and one variable, the circle's radius. Therefore, the formula for calculating a circle's perimeter or circumference is as follows:
Circle Perimeter Formula
A circle's perimeter is equal to 2πr = πD units, where r is the radius of the circle and D is the circle's diameter.
Examples of the perimeter of a circle formula
Example 1: Calculate the circumference or perimeter of the circle whose diameter is 7 inches.
Solution:Given: Diameter of circle = 7 inches
- Using the perimeter of a circle formula,
- The perimeter of a circle = π D
- Perimeter or circumference = 22/7 × 7
- = 22 inch.
Example 2: Find the circle's radius whose circumference of 110 inches.
- Solution: Given: Circumference = 110 in
- From the perimeter of a circle formula,
- The perimeter of the circle = 2 π r
- 2 π r = 110
- 2 × 22/7 × r = 110
- r = 110 × 7 / 44
- r = 17.5 inches.
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