Perimeter and Area Class 6 Notes

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· Jun 27, 2026 · Reviewed & updated Sep 17, 2026 · 3 min read

Perimeter and Area Class 6 Notes

Perimeter and Area Class 6 Notes

1. Perimeter: The perimeter of a polygon is the sum of the lengths of all its sides. It represents the total distance around a closed figure.


2. Area: The area of a closed figure is the measure of the region enclosed by the figure. It is generally measured in square units.


3. Regular Polygon: A regular polygon is a polygon with all sides and angles equal. The perimeter of a regular polygon can be calculated using the formula :

Perimeter = Number of sides × Length of one side.


4. Rectangle: A rectangle is a quadrilateral with opposite sides equal and all angles equal to 90 degrees. The perimeter of a rectangle is calculated as: Perimeter = 2 × (Length + Width).


5. Square A square is a special type of rectangle where all four sides are equal in length. The perimeter of a square is calculated as: Perimeter = 4 × Length of one side.


6. Triangle: A triangle is a polygon with three sides. The perimeter of a triangle is calculated as: Perimeter = Side1 + Side2 + Side 3.


7. Grid Paper: Grid paper is a type of paper printed with a grid of fine lines, used for drawing and measuring shapes, which helps in estimating areas and perimeters.


8. Unit Square: A unit square is a square with a side length of one unit. It is used as a standard measure for calculating area.

9. Closed Figure: A closed figure is a shape where all the sides connect to form a complete boundary, enclosing a space.


10. Estimation of Area: Estimation of area involves approximating the area of a shape by counting the number of unit squares it covers on grid paper.


11. Diagonal: A diagonal is a line segment that connects two non-adjacent vertices of a polygon, particularly in rectangles and squares.


12. Tangram: A tangram is a dissection puzzle consisting of seven flat pieces called tans, which can be arranged to form various shapes.


13. Shape Relationships: This refers to the comparative analysis of different shapes in terms of area and perimeter, such as determining which shape has a larger area or perimeter.


14. Half Square Rule: A guideline used in estimating area on grid paper, where portions of the area that are less than half a square are ignored, and those more than half are counted as a full square.


15. Area of a Triangle: The area of a triangle can be calculated using the formula :

Area = [latex]\frac{1}{2}[/latex] × Base × Height.


Perimeter

What is Perimeter?

Perimeter is the distance around a shape.

Imagine you are walking around the outside of a playground. The total distance you walk is the perimeter of that playground.

To find the perimeter of a shape, you simply add up the lengths of all its sides.


How to Calculate Perimeter:

1. For a Rectangle: A rectangle has two lengths dnd two widths.

The formula for the perimeter (P) of a rectangle is : P = 2 × (Length + Breadth)

2. For a Square: A .square has four equal sides.

The formula for the perimeter (P) of a square is : P = 4 × (Length of a side)

3. For a Triangle: A triangle has three sides.

The formula for the perimeter (P) of a triangle is : P = Side 1 + Side 2 + Side 3


Area

Area is the amount of space inside a shape. Think of it as how much carpet you would need to cover the floor of a room or how much paint you would need to cover a wall.

To find the area of a shape, you measure how many square units can fit inside it.

How to Calculate Area:

1. For a Rectangle : The area (A) of a rectangle is found by multiplying its length by its width.

The formula is : A = Length × Width

2. For a Square: Since all sides of a square are equal, the area is found by multiplying the length of one side by itself.

The formula is : A = Side × Side (or A = Side )


Area of a Triangle

For a Triangle: The area (A) of a triangle is found by taking half of the base times the height. ,

The formula is: A = [latex]\frac{1}{2}[/latex] × Base × Height.