Page 150 - Maths Class 06

Rows

Columns 4 cm 3 cm 6 cm 4 cm 5 cm

7 cm 5 cm 5 cm
(a) (b) (c) (d)

Area = 7 × 4 = 28 sq. cm Area = _______________ Area = _______________ Area = ____________

Count the number of squares of area 1 cm² each, enclosed in the rectangle shown in Fig (a).
Clearly, it contains (4 × 7) such squares, because the figure has 4 rows and each row has 7 squares.

If you count the number of squares in columns, then the total number of squares would be 7 × 4 because
there are 7 columns and each column has 4 squares.
\ Total number of squares = 4 × 7 = 7 × 4
Area of rectangle = (7 × 4) sq. cm

= 28 sq. cm
Thus, area of rectangle = Length × Breadth
Area
Length of rectangle =
Breadth
Area
Breadth of rectangle=
Length

NOTE
If the length and breadth of a rectangle are doubled then its area will increase four times.
A = L × B
A' = 2L × 2B
A = 4 . (L × B)''
A = 4 . A'

Using this method, you can find the areas of rectangles of Figures (b) and (c).
Area of a Square

Since a square a special case of rectangle in which the length is equal to breadth, you can modify the
formula of area for the square as:
2
Area of square = (side × side) = (side) sq. units
EX AM PLE 1. Find the area of the rect an gles whose sides are:
(a) 6 cm and 4 cm (b) 1 m and 500 m (c) 3 m and 80 cm

SOLUTION : Area of a rect an gle = Length × Breadth
(a) Area of rectangle = 6 cm × 4 cm

= 24 sq. cm

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