Question

A room is 9 meter long ,8m broad and 6.5m high. It has on door 3m x 1.5m and three windows each of dimensions 1.5m and 1m. Find the cost of white washing the walls at Rs.3.75 per m2

Answer 1

area of four walls=2(l+b)*h
2(9+8)*6.5=34*6.5=221m²
area of door=3*1.5=4.5m²
area of Windows=3*(1*1.5)=3*1.5=4.5m²
area of walls to be whitewashed=221-4.5-4.5=221-9=212m²
cost of whitewashing=212*3.75=Rs.795
hope it helps

Answer 2

LENGTH= 9m
breadth= 8m
height= 6.5m

For white washing of the walls, only 4 faces out of 6 are to be taken into consideration.

Therefore, Lateral Surface Area of Cuboid= 2h(l+b)

=2x6.5(9+8)
=13x17
=221--->This is the lateral surface area of the room.
To find the cost of white washing of walls, Multiply 221 with 3.75
=221x3.75
=828.75
Therefore, The cost of white washing =Rs.828.75