Page 1 - LN 6.1

SAI International School

CLASS-VI
Mathematics
CHAPTER 6 Perimeter and Area
Lesson Notes 6.1

SUBTOPIC: Perimeter

 PERIMETER: The perimeter of any closed plane figure is the distance
covered along its boundary when you go around it once. For a polygon (a

closed plane figure made up of line segments) the perimeter is simply
the sum of the lengths of its all sides, i.e., the total distance along its
outer boundary.

 The perimeter of a polygon = the sum of the lengths of its all sides.
 PERIMETER OF A RECTANGLE: Sum of the lengths of its four sides.
 Perimeter of a rectangle = length + breadth + length + breadth.
Perimeter of a rectangle = 2 × (length + breadth).

 The perimeter of a rectangle is twice the sum of its length and
breadth.

 EXAMPLE: Akshi wants to put lace all around a rectangular
tablecloth that is 3 m long and 2 m wide. Find the length of the

lace required.
SOLUTION: We need to find the perimeter of the tablecloth for
this question.

So, the perimeter of the rectangular tablecloth
= 2 × (length + breadth) = 2 × (3 m + 2 m) = 2 × 5 m = 10 m
 PERIMETER OF A SQUARE: Perimeter of a square = 4 × length of a side.

 The perimeter of a square is quadruple the length of its side.