Page 113 - Revised Maths Wisdom Class - 6

Perimeter and Area 111

Step 2: Count the number of squares which are more than half enclosed by the figure. Here we have none.
Step 3: Now count the number of squares which are exactly half enclosed by the figure and count them. Here,
no. of half squares are 4.
Step 4: Now, to calculate the required area we use the formula,

h
Estimated Area = f + m + sq. units.

2
Here, f = No. of complete covered squares = 7
Rememb
m = No. of more than half enclosed squares = 0 Remember!er!
h = No. of exactly half enclosed squares = 4 › We may ignore the squares which
4 enclose less than half of a square.
Then, area = 7 + 0 + = 7+ 2 = 9 sq. cm We get an approximate area here.
2

Area of Regular Shapes

We must also learn the way to find the area of regular shapes as often the shapes we use in real-life are regular
and symmetric. For example, tiles, windows, doors, paintings, etc. So, let us find the area of rectangle, square, etc.

Area of Rectangle
Let us take a rectangle ABCD of length 7 cm and breadth 4 cm.
Place this rectangle on the graph paper as shown in figure below.

As you can observe the number of squares covering the rectangle ABCD
completely are 28. Hence, the area of the rectangle = area of 28 squares
= 28 × area of 1 square = 28 × 1 sq. cm

= 28 sq. cm = 7 × 4
= length × breadth
Area of rectangle = length × breadth

Remember!er!
Rememb
› To find length or breadth when area of rectangle is given and any one of its dimensions is also given:
Area Area
Length = , Breadth =
Breadth Length

Area of Square
Let us take a square PQRS of length 6 cm. Place it on the graph paper as shown in figure below.

As you can observe the number of small squares covering the Square
PQRS completely are 36. Hence, the area of the square = Area of
36 squares

= 36 × area of 1 square = 36 × 1 sq. cm
= 36 sq. cm = 6 × 6

= side × side
Area of square = side × side