Page 116 - Revised Maths Wisdom Class - 6

114 MATHS

Area = length × breadth
= 7 × 4.5 sq.m
= 31.5 sq. m

Hence, 31.5 sq. m of carpet is needed to cover the floor.

Example 7: How many tiles of length 16 cm and breadth 5 cm will be required to fit in a rectangular area of
96 cm × 60 cm?
Solution: Area of rectangular region = 96 cm × 60 cm = 5760 cm 2
Area of each tile = 16 × 5 sq. cm = 80 sq. cm

Area of rectangular region 576 0
No. of tiles = = = 72
Area of each tile 80

Hence, the number of tiles required is 72.

Example 8: The area of a square park is the same as that of a rectangular park. If the side of the square park is
70 m and the length of the rectangular park is 140 m, find its breadth.
Solution: Area of rectangular park = Area of square park
Let the breadth be ‘b’

⇒ l × b = side × side
side × side 70 × 70
⇒ b = = = 35 m
l 140
Hence, the breadth of rectangular park is 35 m.

Example 9: Six square flower beds each of size 2.5 m are dug on a piece of land 15 m long and 10 m wide. Find
the area of the remaining part of land.
Solution: Length of land = 15 m
Breadth of land = 10 m

Area of land = l × b = 15 × 10 sq. m = 150 sq. m
Area of 1 square bed = 2.5 × 2.5 = 6.25 sq. m
Area of 6 square beds = 6 × 6.25 = 37.50 sq. m

Area of remaining part of land = Area of land – Area of 6 square flower beds
= 150 – 37.50 = 112.50 sq. m.

Exercise 7B
Exercise 7B
1. Find the areas of the following irregular figures. Assume that each small square is 1 cm .
2
(a) (b) (c)