Circumference Study Guide

The circumference of a circle is the distance around the edge of the circle. It is like the perimeter of other shapes, but specifically for circles.

Formula for Circumference

The formula to find the circumference of a circle is:

Circumference = 2 × π × r

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

Understanding the Components

The radius of a circle is the distance from the center of the circle to any point on its edge. It is half of the diameter. So, in the formula, 2 × r is the diameter of the circle, and multiplying it by π gives us the circumference.

Example

If the radius of a circle is 5 units, then the circumference would be:

Circumference = 2 × 3.14159 × 5

Circumference = 31.4159 units

Study Tips

Memorize the formula: Circumference = 2 × π × r
Practice using the formula with different radius values
Understand the relationship between radius, diameter, and circumference

◂Math Worksheets and Study Guides Fifth Grade. Probability

The resources above cover the following skills:

Number and Operations (NCTM)

Understand numbers, ways of representing numbers, relationships among numbers, and number systems.

Develop understanding of fractions as parts of unit wholes, as parts of a collection, as locations on number lines, and as divisions of whole numbers.

Algebra (NCTM)

Use mathematical models to represent and understand quantitative relationships.

Model problem situations with objects and use representations such as graphs, tables, and equations to draw conclusions.

Data Analysis and Probability (NCTM)

Understand and apply basic concepts of probability.

Describe events as likely or unlikely and discuss the degree of likelihood using such words as certain, equally likely, and impossible.

Understand that the measure of the likelihood of an event can be represented by a number from 0 to 1.