Page 227 - ICSE Math 6

Area of a square (using a squared paper)

Squared paper is a paper that has squares of side 1 cm drawn on it. 1 cm 2 1 cm
2
The area of a square of side 1 cm is 1 cm . 1 cm
Now, we will find the area of a square using a squared paper. Draw the outline of the square on a
squared paper. Count the number of squares inside the outline of the square. There are 9 squares.
Area of square = Area of 9 squares
2
= 9 × 1 cm = 9 cm 2
Side of square = Sum of the sides of 3 squares
= 3 cm
2
Thus, the area of square = 9 cm = 3 cm × 3 cm
= side × side

Hence, area of a square = (length of a side) 2
So, if the length of each side of a square is a units, then its area (A) is
2
given by the formula A = a .
Area of a rectangle (using a squared paper)

We can also find the area of a rectangle using a squared paper. Draw the outline of the rectangle on a
squared paper. Count the number of squares inside the outline of the rectangle. There are 10 squares.
Area of rectangle = Area of 10 squares
2
= 10 × 1 cm = 10 cm 2
Length of rectangle = Sum of the sides of 5 squares
= 5 cm
Breadth of rectangle = Sum of the sides of 2 squares
= 2 cm
2
Thus, area of the rectangle = 10 cm = 5 cm × 2 cm
= length × breadth
So, if the length of a rectangle is l units and the breadth is b units, then its area (A) is given by the
formula A = l × b.
A A
Also, l = and b = .
b l

While finding perimeter and area, unit for measurement of each side must be the same.

Conversion of Units
The table shows the relation between different units of mass, length, time, money and capacity.
MASS MONEY CAPACITY
1 kg = 1,000 g ` 1 = 100 paise 1 L = 1,000 mL
TIME LENGTH

1 year = 365 days 1 km = 1,000 m
1 day = 24 hours 1 m = 100 cm
1 hour = 60 minutes 1 cm = 10 mm
1 minute = 60 seconds 1 foot = 12 inches

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