Perimeter
The perimeter of a shape is the distance around the outside of the shape. It is the total length of all the sides of the shape added together.
The formula to find the perimeter of different shapes are:
- For a square or rectangle: P = 2(l + w), where P is the perimeter, l is the length, and w is the width.
- For a triangle: P = a + b + c, where P is the perimeter, and a, b, c are the lengths of the three sides.
- For a circle: P = 2πr, where P is the perimeter, and r is the radius of the circle.
It is important to include the units when expressing the perimeter, such as inches, centimeters, or any other unit of length.
Understanding the concept of perimeter helps in measuring the boundary of a shape, determining the amount of material needed to enclose a space, or calculating the distance around an object.
.◂Math Worksheets and Study Guides Third Grade. Symmetry
Study Guide
Symmetry 
Worksheet/Answer key
Symmetry Worksheet/Answer key
Symmetry Worksheet/Answer key
Symmetry Worksheet/Answer key
Congruence and Symmetry
Worksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyThe 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.
Identify, compare, and analyze attributes of two- and three-dimensional shapes and develop vocabulary to describe the attributes.
Apply transformations and use symmetry to analyze mathematical situations.
Identify and describe line and rotational symmetry in two- and three-dimensional shapes and designs.