Area of Rectangle (Grade 4)
The area of a rectangle tells you how much surface it covers. Instead of counting every square on a grid, you can use a formula: multiply the length by the breadth.
In Class 4, you will learn the formula for the area of a rectangle, how to apply it in word problems, and how to find a missing side when the area is given.
What is Area of Rectangle - Class 4 Maths (Measurement)?
The area of a rectangle is the number of square units that fit inside it. Since a rectangle has rows and columns of unit squares, the area equals the number of rows multiplied by the number of columns.
Area of Rectangle (Grade 4) Formula
Area of Rectangle = Length × Breadth
If the length is in cm, the area will be in sq cm (cm²). If the length is in m, the area will be in sq m (m²).
To find a missing side: Length = Area ÷ Breadth or Breadth = Area ÷ Length.
Solved Examples
Example 1: Example 1: Basic area calculation
Problem: Find the area of a rectangle with length 9 cm and breadth 5 cm.
Solution:
Step 1: Area = Length × Breadth
Step 2: Area = 9 × 5 = 45 sq cm
Answer: The area is 45 sq cm.
Example 2: Example 2: Area of a classroom floor
Problem: A classroom is 10 m long and 8 m wide. Find the area of the floor.
Solution:
Step 1: Area = 10 × 8 = 80 sq m
Answer: The floor area is 80 sq m.
Example 3: Example 3: Finding breadth from area
Problem: The area of a rectangular garden is 72 sq m. The length is 12 m. Find the breadth.
Solution:
Step 1: Breadth = Area ÷ Length
Step 2: Breadth = 72 ÷ 12 = 6 m
Answer: The breadth is 6 m.
Example 4: Example 4: Finding length from area
Problem: A rectangular card has area 56 sq cm and breadth 7 cm. Find the length.
Solution:
Step 1: Length = Area ÷ Breadth = 56 ÷ 7 = 8 cm
Answer: The length is 8 cm.
Example 5: Example 5: Tiling a floor
Problem: Ria's room is 6 m long and 4 m wide. Each tile covers 1 sq m. How many tiles are needed?
Solution:
Step 1: Area of room = 6 × 4 = 24 sq m
Step 2: Each tile = 1 sq m. Number of tiles = 24.
Answer: Ria needs 24 tiles.
Example 6: Example 6: Cost of painting
Problem: A rectangular wall is 5 m long and 3 m high. Painting costs ₹15 per sq m. Find the total cost.
Solution:
Step 1: Area = 5 × 3 = 15 sq m
Step 2: Cost = 15 × ₹15 = ₹225
Answer: The painting cost is ₹225.
Example 7: Example 7: Comparing areas
Problem: Rectangle A is 12 cm × 4 cm. Rectangle B is 8 cm × 6 cm. Which has a larger area?
Solution:
Step 1: Area of A = 12 × 4 = 48 sq cm
Step 2: Area of B = 8 × 6 = 48 sq cm
Answer: Both rectangles have the same area: 48 sq cm. (Different dimensions can give the same area.)
Example 8: Example 8: Area and perimeter together
Problem: A rectangle has length 14 cm and breadth 6 cm. Find both area and perimeter.
Solution:
Step 1: Area = 14 × 6 = 84 sq cm
Step 2: Perimeter = 2 × (14 + 6) = 2 × 20 = 40 cm
Answer: Area = 84 sq cm, Perimeter = 40 cm.
Example 9: Example 9: Carpet for a room
Problem: Arjun wants to lay carpet in a room that is 7 m long and 5 m wide. Carpet costs ₹120 per sq m. How much will it cost?
Solution:
Step 1: Area = 7 × 5 = 35 sq m
Step 2: Cost = 35 × ₹120 = ₹4,200
Answer: The carpet will cost ₹4,200.
Example 10: Example 10: Word problem
Problem: A rectangular playground is 50 m long and 30 m wide. A path 2 m wide runs along the inside boundary. Find the area of the path.
Solution:
Step 1: Area of whole playground = 50 × 30 = 1,500 sq m
Step 2: Inner length = 50 − 2 − 2 = 46 m. Inner breadth = 30 − 2 − 2 = 26 m.
Step 3: Area of inner region = 46 × 26 = 1,196 sq m
Step 4: Area of path = 1,500 − 1,196 = 304 sq m
Answer: The area of the path is 304 sq m.
Key Points to Remember
- Area of Rectangle = Length × Breadth.
- Area is measured in square units (sq cm, sq m).
- To find a missing side: divide the area by the known side.
- Rectangles with different dimensions can have the same area.
- Area is used for tiling, painting, carpet-laying, and farming.
- Always include the correct unit (sq cm, sq m) in your answer.
Practice Problems
- Find the area of a rectangle with length 15 cm and breadth 9 cm.
- A rectangular farm is 80 m long and 50 m wide. What is its area?
- The area of a rectangle is 96 sq cm. Its breadth is 8 cm. Find the length.
- Priya wants to cover a table top measuring 120 cm × 80 cm with paper. How much paper does she need?
- A room is 6 m × 4 m. Floor tiles cost ₹50 per sq m. What is the total cost?
- Two rectangles have areas of 36 sq cm each. One is 9 cm × 4 cm. What could be the dimensions of the other?
- Find the area and perimeter of a rectangle with length 20 cm and breadth 12 cm.
Frequently Asked Questions
Q1. What is the formula for the area of a rectangle?
Area of a rectangle = Length × Breadth. The answer is in square units (sq cm if sides are in cm, sq m if sides are in m).
Q2. Why do we multiply length by breadth?
A rectangle can be divided into rows and columns of unit squares. The number of rows times the number of columns gives the total squares, which equals the area.
Q3. How do you find a missing side of a rectangle?
Divide the area by the known side. If area = 48 sq cm and length = 8 cm, then breadth = 48 ÷ 8 = 6 cm.
Q4. What units are used for area?
Area is measured in square units: sq cm (cm²) for small surfaces, sq m (m²) for rooms and fields, and sq km (km²) for very large areas.
Q5. Can two rectangles with the same area have different perimeters?
Yes. A 12 × 3 rectangle and a 9 × 4 rectangle both have area 36 sq cm, but their perimeters are 30 cm and 26 cm respectively.
Q6. Is area of a rectangle always greater than its perimeter?
Not necessarily. For a 2 cm × 3 cm rectangle, area = 6 sq cm and perimeter = 10 cm. Area and perimeter use different units, so direct comparison is not meaningful.
Q7. How is the area of a rectangle related to the area of a square?
A square is a special rectangle where length = breadth. So the area of a square = side × side, which is the same as the rectangle formula with l = b.
Q8. What real-life problems use the area of a rectangle?
Calculating floor tiles, wall paint, carpet, cloth for a table cover, and the size of a cricket pitch or football field all use the area of a rectangle.
Related Topics
- Introduction to Area
- Area of Square (Grade 4)
- Perimeter (Grade 4)
- Area and Perimeter Word Problems (Grade 4)
- Converting Units of Length (Grade 4)
- Converting Units of Weight (Grade 4)
- Converting Units of Capacity (Grade 4)
- Area by Counting Squares
- Perimeter of Irregular Shapes
- Relationship Between Area and Perimeter
