The circumference of a circle is the distance around the edge of the circle. It is similar to the perimeter of other shapes, such as rectangles or squares, but specifically refers to the distance around a circle.

The formula for finding the circumference of a circle is:

C = 2πr

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

**Understand the concept:**Make sure you understand that the circumference is the distance around the circle, and how it is different from the area of the circle.**Learn the formula:**Memorize the formula C = 2πr, and understand what each symbol represents.**Practice with examples:**Work through practice problems to calculate the circumference of circles with different radii.**Use π (pi):**Understand the significance of π and how it is used in the formula to find the circumference.**Real-life applications:**Look for real-life examples where understanding the circumference of a circle is important, such as in engineering or design.

By understanding the concept of circumference and practicing with the formula, you can become proficient in calculating the distance around a circle.

.Study GuideArea and Circumference of Circles Activity LessonArea of Circles Activity LessonCircumference of Circles Worksheet/Answer key

Area and Circumference of Circles Worksheet/Answer key

Area and Circumference of Circles Worksheet/Answer key

Area and Circumference of Circles Worksheet/Answer key

Area and Circumference of Circles

Geometry (NCTM)

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.

Connections to the Grade 6 Focal Points (NCTM)

Measurement and Geometry: Problems that involve areas and volumes, calling on students to find areas or volumes from lengths or to find lengths from volumes or areas and lengths, are especially appropriate. These problems extend the students' work in grade 5 on area and volume and provide a context for applying new work with equations.