Class 3 Mathematics
Perimeter and Area Class 3 Worksheet with Online Activities & Quiz
Measure the distance around shapes, count the squares inside them and solve short word problems on perimeter and area.
Explore WitKnowLearn’s perimeter and area worksheet for Class 3 with online quiz and online activities. Walk round the edge of a shape to find its perimeter, count unit squares to find its area, and solve short word problems about gardens, fences and floors. Every activity uses a grid or shape you can tap.
Perimeter and Area Online Quiz for Class 3
Perimeter and Area Online Activities for Class 3
Perimeter and Area for Class 3: complete topic guide
What is perimeter?
Perimeter is the distance all the way around a shape. To find it, add the lengths of all the sides. It is measured in units of length such as centimetres (cm) and metres (m).
Perimeter of common shapes
| Shape | How to find the perimeter | Example |
|---|---|---|
| Triangle | Add the 3 sides | 3 + 4 + 5 = 12 cm |
| Rectangle | Length + width + length + width | 8 + 5 + 8 + 5 = 26 cm |
| Square | 4 × side | 4 × 6 = 24 cm |
What is area?
Area is the amount of flat space inside a shape. We find it by counting how many unit squares cover the shape. Area is measured in square units such as square centimetres (sq cm).
Area of a rectangle
A rectangle is made of rows of unit squares. The number of rows is the width and the number of squares in each row is the length. So area = length × width. A rectangle 7 cm long and 4 cm wide has an area of 7 × 4 = 28 sq cm.
Perimeter and area are different
Perimeter is about the edge and uses a length unit. Area is about the inside and uses a square unit. Two shapes can have the same area but different perimeters. A 4 by 3 rectangle and a 6 by 2 rectangle both have an area of 12 sq cm, but their perimeters are 14 cm and 16 cm.
Solved examples
Common mistakes
| Mistake | Correction |
|---|---|
| Adding only two sides of a rectangle | Add all four sides, or double length + width. |
| Writing area in cm | Area uses square units such as sq cm. |
| Adding length and width to find area | Area is length × width. |
| Counting inside squares for perimeter | Perimeter counts only the edge lengths. |
| Using one side of a square as its perimeter | A square has 4 equal sides, so multiply by 4. |
Perimeter and area in daily life
We use perimeter for a fence round a garden, a border on a notice board or a walk round a park. We use area for tiles on a floor, carpet in a room or paint on a wall.
Related Maths Worksheets
- Multiplication worksheets for Class 3Rows and columns of squares
- Geometry Class 3 worksheet with online activities and quizShapes and their sides
- Measurement Long and Short worksheet for Class 3Measure lengths in cm and m
- Measurement of Weight worksheet for Class 3More Class 3 measurement
- Fractions Class 3 worksheet with online activities and quizParts of a whole
- Data Handling Class 3 worksheet with online activities and quizRead and draw simple charts
- Addition and Subtraction word problems for Class 3Add side lengths and solve stories
- 2D and 3D Shapes worksheets for Class 2Revise shapes
- Measurement worksheets for Class 2 with online activitiesRevise length
- Measurement worksheet for Class 4Extend measurement
- Tables and Shares worksheet for Class 4Extend multiplication
- How Heavy How Light worksheet for Class 4Extend measurement
Frequently Asked Questions
What is perimeter for Class 3?
Perimeter is the distance around a shape. Add the lengths of all its sides.
What is area for Class 3?
Area is the amount of flat space inside a shape. We count unit squares to find it.
Which units are used for perimeter and area?
Perimeter uses units of length such as cm and m. Area uses square units such as sq cm.
How do I find the perimeter of a rectangle?
Add length + width + length + width. A rectangle 8 cm by 5 cm has a perimeter of 8 + 5 + 8 + 5 = 26 cm.
How do I find the perimeter of a square?
Multiply one side by 4. A square with side 6 cm has a perimeter of 4 × 6 = 24 cm.
How do I find the perimeter of a triangle?
Add its three sides. Sides of 3 cm, 4 cm and 5 cm give 3 + 4 + 5 = 12 cm.
How do I find the area of a rectangle?
Multiply length by width. A rectangle 7 cm by 4 cm has an area of 7 × 4 = 28 sq cm.
How do I find the area by counting squares?
Count the unit squares that cover the shape. For a rectangle, multiply the number of rows by the number of squares in each row.
Can two shapes have the same area but different perimeters?
Yes. A 4 by 3 rectangle and a 6 by 2 rectangle both cover 12 squares, but their perimeters are 14 cm and 16 cm.
How do I find a missing side from the perimeter?
Subtract the known sides from the perimeter. For a rectangle, half the perimeter is length + width, so subtract the known side from that.
How do I find a missing side from the area?
Think of a multiplication fact. If the area is 24 sq cm and the length is 6 cm, then 6 × 4 = 24, so the width is 4 cm.
How do I solve a perimeter or area word problem?
Ask whether the problem is about the edge or the inside. Fences, borders and walks are perimeter. Tiles, carpets and paint are area.
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