Question

Question 65

The walls and ceiling of a room are to be plastered. The length, breadth and height of the room are 4.5 m, 3 m and 350 cm respectively. Find the cost of plastering at the rate of Rs. 8 per $m^2$.

Answer 1

Given, length of the room (l) = 4.5 m
Breadth of the room (b) = 3 m
Height of the room (h) = 350 cm = 3.5 m [$\because$ 100 cm = 1m]
and the cost of plastering = Rs. 8 per $m^2$
$\therefore$ Area of the walls = 2h(l + b)
$=2\times 3.5(4.5+3)$
$=7\times \left(7.5\right)=52.5m^2$
Area of the ceiling = lb = $4.5\times 3=13.5m^2$
Area of the room = 52.5 + 13.5 $=66m^2$
Hence, the cost of plastering $=66\times 8=Rs.528$