9. A room is 12 m long, 8 m broad and 4 m high. It has two
doors, each measuring 2.2 m by 1.6 m and two windows,
each measuring 2.4 m by 2.2 m. Find the cost of white
washing its four walls at 7.70 per sqm.
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Answers
Answer:
1096.48 Rs
Step-by-step explanation:
Room Dimensions are below:
L=12 m
B=8 m
H=4 m
Total Surface Area of room wall = 2(L x H)+ 2 (B x H)
= 2 (12 x 4) + 2(8 x 4)
= 2 (48) + 2(32)
= 96 + 64
= 160 sq. meter
Let suppose total area of walls denoted by A= 160 Sq. meter
Area of Doors calculation:
L= 2.2 m
B= 1.6 m
Area of One door = L x B
= 2.2 x 1.6
=3.52 sq. meter
Therefore, in given question there are total two doors,
So, Total area of Two doors = 2 x 3.52
=7.04 Sq. meter
Let suppose area of two doors denoted by A1 = 7.04 Sq. meter
Area of Windows calculation:
L=2.4 m
B=2.2 m
Area of One Window = L x B
= 2.4 x 2.2
=5.28 sq. meter
Therefore, in given question there are total two windows,
So, Total area of Two windows = 2 x 5.28
=10.56 Sq. meter
Let suppose area of two windows denoted by A2 = 10.56 Sq. meter.
According to the given condition, we need to find out the cost at which white paint is being consumed. So, we have to find out the net area ΔA which is consist of wall other then the doors and windows.
ΔA= A - (A1 + A2)
ΔA= 160 - (7.04 + 10.56)
ΔA= 160 - (17.6)
ΔA= 142.4 Sq. meter
Cost Calculation:
As given cost per Sq. meter = 7.7 Rs
Required cost of 142.4 sq. meter = 142.4 x 7.7
=1096.48 Rs
The total cost of white washing its four wall would be 1096.48 Rs.
Step-by-step explanation: