1. Perimeter

2. Perimeter The perimeter of a closed figure is
the total measure of the boundry.
Rahman is a farmer. He has to fence his field
What length of the barbed wire I should buy to fence my field?
The answer is,
I should buy 8 m + 12 m +10 m + 4 m = 34 m barbedwire.

3. First we need to find he length of each side by counting the squares.
8 cm
The distance around the outside of a shape is called the perimeter.
6 cm
6 cm
8 cm
The perimeter of the shape is = 28cm.

4. Perimeter of a Rectangle2 4
Perimeter
= 12
To calculate the perimeter of an object or space, you will
need to add the length and width, then multiply by 2.
= 2 (length + breadth)
=2 x ( ) = 12

5. Perimeter of Rectangle Formula
We know that, the perimeter of rectangles with
different lengths and breadths is length + breadth +
length + breadth
Perimeter = 2 x length + 2 x breadth
= 2 (length + breadth)
= 2 (l + b) units
where ‘l’ denotes the length and ‘b’ denotes the breadth.
So, Perimeter of a rectangle = 2 (l + b) units

6. Example 1: Find the perimeter of a rectangle, whose length is 6 cm and breadth is 2 cm. Solution: Method 1: Perimeter = Length + Breadth +Length +Breadth = = 16cm Method 2: Perimeter = 2 x (l+b) units = 2 x (6+2) = 2 x 8 = 16 cm 6 2

7. Example 2:Find the perimeter of a rectangle, whose length is 8 cm and breadth is 4 cm.
Solution:
Method 1:
Perimeter = Length + Breadth +Length +Breadth
= = 24cm
Method 2:
Perimeter = 2 x (l+b) units
= 2 x (8+4)
= 2 x 12 = 24 cm

8. To find the perimeter of
Perimeter of a Square
Perimeter
To find the perimeter of
a square, multiply the
side by 4.
3 x 4 = 12 3

9. Perimeter of Square using Formula
Every square is a rectangle whose length and
breadth are equal.
Perimeter = 2 x side + 2 x side
= 4 x side
= 4s, where‘s’ is the side.
So, Perimeter of a square = 4 x side units

10. Example 1: Find the perimeter of a square whose side is 20 cm.
Solution:
Method 1:
Perimeter = side + side + side + side =
= 80 cm
Method 2:
Perimeter = 4 x side = 4 x 20 = 80 cm 20

11. Example 1: Find the perimeter of a square whose side is 24 cm
Example 1: Find the perimeter of a square whose side is 24 cm. Solution: Method 1: Perimeter = side + side + side + side = = 96 cm Method 2: Perimeter = 4 x side = 4 x 24 = 96 cm

12. Perimeter of a Triangle4 3 5
To calculate the perimeter of a triangle
you will need to add the sides.
= 12 (Just add all three sides)

13. Find the perimeter of the following triangles6 5 4 6 8 7 4
To calculate the perimeter
of a triangle, you will need
to add the sides.
= 15 (Just add
all three sides)
To calculate the perimeter
of a triangle, you will need
to add the sides outside.
= 21 (Should not
take 4 as 4 is inside the
triangles)

14. Try these
Find the perimeter of the given shapes 2 5 12 3 4