Mathematics
A room is 3 m long, 2 m broad and 2 m high. It has one door 2 m x 1 m; two windows each 1 m x 0.5 m; the remaining area of the walls is :
16 m2
17 m2
20 m2
5 m2
Surface Area, Volume, Capacity
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Answer
Given:
Dimensions of the room are 3 m long, 2 m broad and 2 m high.
Dimensions of the door are 2 m x 1 m.
Dimensions of the windows are 1 m x 0.5 m.
Remaining area = Total surface area of room - (Area of door + Area of window)
Total surface area of room = 2(l + b)h
= 2(3 + 2)2 m2
= 2 x 5 x 2 m2
= 20 m2
Area of door = l x b
= 2 x 1 m2
= 2 m2
Area of window = l x b
Area of two window = 2 x l x b
= 2 x 1 x 0.5 m2
= 1 m2
Remaining area = 20 - (2 + 1) m2
= 20 - 3 m2
= 17 m2
Hence, option 2 is the correct option.
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