Perimeter Introduction for 3rd Grade

The perimeter is the total distance around the outside of a shape.

To find the perimeter of a rectangle, add the lengths of all four sides or use the formula: P = 2(length + width).

The unit of measurement for perimeter can be centimeters (cm), meters (m), inches (in), or feet (ft).

The perimeter is 16 cm (P = 4 sides x 4 cm).

The perimeter is 12 cm (3 + 4 + 5 = 12).

You add the lengths of all the sides of the shape.

The perimeter is 10 cm (2 + 3 + 5 = 10).

The perimeter is 16 cm (P = 2(6 + 2) = 16).

The perimeter is 20 units (P = 4 sides x 5 units).

The formula for the perimeter of a rectangle is P = 2(length + width).