A room is 12 m long, 8 m wide and 5.5 m high. It has one door of dimensions 2.5 x 2 m and 2 windows each of dimensions 1.2 m x 1 m. Find the cost of white-washing the walls at Rs 2.70 per sq. metre.
Answers
Given :-
- Length of a room ( L ) = 12 m
- Breadth of a room ( B ) = 8 m
- Height of a room ( H ) = 5.5 m
- Area of 1 door = 1× (2.5 × 2m)
- Area of 2 windows = 2× ( 1.2 × 1m)
To find :-
the cost of white-washing the walls at Rs 2.70
per sq. metre.
solution :-
Length of a room ( L ) = 12 m
Breadth of a room ( B ) = 8 m
Height of a room ( H ) = 5.5 m
Area of 4 walls = 2 h ( l + b )
= 2 × 5.5 ( 12 + 8 )
= 11.0 ( 20 ) = 220 sq.m
Area of 1 door = 1 × ( 2.5 × 2 )
= 5 sq.m
Area of 2 windows = 2 × ( 1.2× 1 )
= 2.4 sq.m
Area of walls to be white - washed
= 220 - ( 5 + 2.4 )
= 220 - 7.4 sq.m
= 212.6 sq.m
Cost of white - washing 1 sq.m = Rs 2.70
Cost of white - washing 212.6 sq.m
= Rs 2.70 × 212.6
= Rs 574.02
Hence,
Cost of white - washing 212.6 sq.m = 574.02
Given :-
● A room is 12m long, 8m wide and 5.5m high
● Dimensions of one room = 2.5 * 2
● Dimension of each window 1.2m * 1m
Solution :-
Area of 4 walls = 2 ( l + b)h
Put the required values in the given formula,
TSA of room = 2(12 + 8)5.5
TSA of room = 2 * 20 * 5.5
TSA of room = 40 * 5.5
TSA of room = 220m^2
Now,
Area of 2 window = 2 * ( 1.2 * 1 )
Area of 2 window = 2 * 1.2
Area of 2 window = 2.4m
Now,
Area of 1 door = 2.5 * 2
Area of 1 door = 5m
Therefore,
Area of walls to be whitewashed = Area of 4 walls - Area of door - Area of 2 window
Put the required values,
Area of walls to be whitewashed
= 220 - 5 - 2.4
Area of walls to be whitewashed = 212.6m^2
Now,
We have to find the cost of white washing
Therefore,
The cost of white washing the walls
= 212.6 * 2.70
= 574.02m^2