Page 115 - Revised Maths Wisdom Class - 6

Perimeter and Area 113

Solution: Figure Fully-filled More than Half-filled Less than Estimated area
squares (f) half-filled squares (h) half-filled h
squares (m) squares (l) f m 2

sq. units
(i) 10 0 2 0 11
(ii) 3 0 6 0 6

(iii) 2 2 2 2 5
(iv) 0 3 2 7 4

(v) 1 2 5 2 5.5
(vi) 4 4 1 10 8.5

Example 3: A rectangular field has length and breadth as 19.8 m and 5.7 m respectively. Find the area of the
field.
Solution: Length of rectangular field = 19.8 m
Breadth of rectangular field = 5.7 m
Area of rectangle = l × b = 19.8 × 5.7 = 112.86 m 2
Hence, area of its field is 112.86 m .
2
Example 4: Find the cost of tiling a rectangular piece of land 600 m long and 250 m wide at the rate of ` 10 per
hundred sq. m.
Solution: Length of rectangular plot = 600 m
Breadth of rectangular plot = 250 m
Area of rectangle = length × breadth

= 600 × 250 = 150000 sq. m
Cost of tiling per hundred sq. m = ` 10
10
Cost of tiling 1 sq. m = `
100
10
Cost of tiling 150000 sq. m = ` × 150000 = ` 15000
100
Hence, the required cost of tiling is ` 15000.

Example 5: The perimeter of a square is 184 cm. Find the area of the square.
Solution: Given perimeter of a square = 184 cm
184
Perimeter of a square = 4 × side ⇐ side = 4 = 46 cm

Also, area of square = side × side
= 46 × 46 = 2116 sq. cm
Hence, the required area is 2116 sq. cm

Example 6: A room is 7 m long and 4 m 50 cm wide. How many square metres of carpet is needed to cover the
floor of room?
Solution: Length of room = 7 m

Breadth of room = 4 m 50 cm = 4.5 m