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Example 1: Find the area of a rectangular postcard whose length is 18 cm and breadth is
12 cm. 18 cm

Solution: Here, length of the postcard = 18 cm POSTCARD
from:
and breadth of the postcard = 12 cm. 12 cm
Area of the postcard = Length × Breadth to:

= 18 cm × 12 cm = 216 sq. cm
Example 2: The area of a rectangle is 1680 sq. cm and its length is 60 cm. Find its breadth.

Solution: Given, area of the rectangle = 1680 sq. cm
and length of the rectangle = 60 cm.

Area 1680 sq. cm
Breadth of the rectangle = = = 28 cm
Length 60 cm
Thus, the breadth of the rectangle is 28 cm.

Example 3: Find the length of a rectangular park whose area is 324 sq. m and breadth is
12 m.
Solution: Area of the park = 324 sq. m

Breadth of the park = 12 m

So, length of the park = Area = 324 m
Breadth 12
= 27 m.
Thus, the length of the park is 27 m.

Example 4: The floor of a room measures 10 m × 8 m. Suresh wants to pave the floor with
tiles. If the cost of paving tiles is `125 per sq.m, then what is the total cost of paving the floor?
Solution: Length of the floor = 10 m

Breadth of the floor = 8 m
Area of the floor = 10 m × 8 m = 80 sq. m

Cost of 1 sq. m of tiling = `125
Cost of 80 sq. m of tiling = `125 × 80

= `10,000
Thus, the total cost of paving the floor is `10,000.

Area of a Square
A D
In the given figure, ABCD is a square. We know that a square is a rectangle
whose length and breadth both are equal. Side

Area of a square = side × side sq. units
B Side C
Teacher’s Ensure that the students understand the difference between perimeter and area. An area is the measure of
Tip the interior region of a closed plane figure, while perimeter is the measure of its boundary. The area and
perimeter of an open plane figure have no meaning.

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