Page 170 - Math Skill - 5

168 Maths

The figure given alongside is covering 10 complete (whole)
squares and 6 half-squares.

We can treat 6 half-squares as 3 whole squares.
So, the area of the figure = 10 + 3 = 13 square units.

Area of a Rectangle
Fact-o-meter
Formula for finding the area of a rectangle is
The length and breadth
Area of a rectangle = length × breadth must have the same

Symbolically, it can be written as, A = l × b unit calculate the area.

where, l = length, b = breadth

Area Area
Length = or Breadth=
Breadth Length
Area of a Square

Square is a special kind of rectangle having all its sides as equal. So, the area of a square is
obtained by finding the product of any of its two sides.

Area of the square = side × side

The area of the square PQRS = PS × SR

Since, PS = SR
The area of PQRS = PS × PS

Let’s Attempt

Example 1: Find the area of a rectangle if its length is 15 cm and breadth is 6 cm.

Solution: We have l = 15 cm, b = 6 cm
We know that, area = length × breadth = 15 cm × 6 cm = 90 sq cm.

Thus, the area of the rectangle is 90 sq cm.

Example 2: Find the area of a square having sides as 11.4 cm.
Solution: Side of the square = 11.4 cm

We know that, area = side × side = 11.4 cm × 11.4 cm = 129.96 sq cm.

Thus, the area of a square is 129.96 sq cm.
Example 3: The floor of a room 8 m long and 3 m broad is to be paved with tiles each having
a length of 20 cm and a breadth of 15 cm. Find the number of tiles required to
cover the floor.

Solution: First express all the quantities into same units

Length of the floor = 8 m = 8 × 100 cm = 800 cm