- p. 3Perimeter on a Grid. Count the unit lengths around each shape, then write the perimeter.
- p. 4Add the Sides. Add the lengths of all the sides to find each perimeter.
- p. 5Shapes with More Sides. Each shape has 7 to 10 sides, so add every side to find the perimeter.
- p. 6Rectangle Sides Match. Write the missing side lengths, then find the perimeter.
- p. 7Find the Missing Side. Use the perimeter to find the length of the side marked with a question mark.
- p. 8Perimeter Stories. Draw and label a picture, then solve each problem.
- p. 14Mixed Review. Read each problem, then solve.
The standard
Determine the perimeter of a polygon and explain that the perimeter represents the distance around a polygon. Solve problems involving perimeters of polygons.
Element 3.GSR.8.1 of Georgia's K-12 Mathematics Standards (2021, effective SY2023-24), in the Geometric & Spatial Reasoning strand. It sits under standard 3.GSR.8: Determine the perimeter of a polygon presented in real-life, mathematical problems.
What students practice
Students count unit lengths around shapes on a grid, add labeled sides on polygons with three to ten sides, use matching opposite sides of rectangles, find a missing side from the perimeter, and solve perimeter stories. No formula is taught.
Where to find it
Think: add the sides in any order, so 4 + 6 + 5 = 10 + 5 = 15 inches.