Question

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 square metre.

Answer 1

Given details are,

Length of room = 4.5m

Breadth of wall = 3m

Height of wall = 350cm = 350/100 = 3.5m

Area of ceiling = l × b

= 4.5 × 3

= 13.5 m²

Area of walls = 2 (lh + bh) m²

= 2 (4.5×3.5 + 3×3.5)

= 2 (15.75 + 10.5)

= 52.5 m²

Sum of Area of ceiling + area of walls = 13.5m² + 52.5m²

= 66m²

Given, Cost for plastering 1m² area = Rs 8

∴ Cost for plastering 66 m² area = 66 × 8 = Rs 528