Circumference

The circumference of a circle is the distance around the circle. It can be found using the formula:

Circumference (C) = 2 * π * r

Where π (pi) is a constant approximately equal to 3.14159, and r is the radius of the circle.

How to find the circumference of a circle

Measure the radius of the circle. The radius is the distance from the center of the circle to any point on the circle.
Use the formula C = 2 * π * r, where π is a constant (approximately 3.14159) and r is the radius of the circle.
Plug in the value of the radius into the formula and calculate the circumference.

Example

Let's find the circumference of a circle with a radius of 5 units.

Circumference (C) = 2 * π * 5

C = 2 * 3.14159 * 5

C ≈ 31.4159 units

Study Guide

When studying the topic of circumference, make sure to:

Understand the concept of circumference as the distance around a circle.
Memorize the formula for finding the circumference of a circle: C = 2 * π * r
Practice calculating the circumference using different values of radius.
Understand the relationship between the circumference and the diameter of a circle (C = π * d).

It's also important to remember the value of π (approximately 3.14159) and how it relates to the circumference of a circle.

Good luck with your studies!

◂Math Worksheets and Study Guides Eighth Grade. Perimeter and area

The resources above cover the following skills:

Geometry (NCTM)

Analyze characteristics and properties of two- and three-dimensional geometric shapes and develop mathematical arguments about geometric relationships.

Precisely describe, classify, and understand relationships among types of two- and three-dimensional objects using their defining properties.

Use visualization, spatial reasoning, and geometric modeling to solve problems.

Use geometric models to represent and explain numerical and algebraic relationships.

Measurement (NCTM)

Apply appropriate techniques, tools, and formulas to determine measurements.

Select and apply techniques and tools to accurately find length, area, volume, and angle measures to appropriate levels of precision.

Develop and use formulas to determine the circumference of circles and the area of triangles, parallelograms, trapezoids, and circles and develop strategies to find the area of more-complex shapes.