Question

The total area of four walls of a room is 660m and the length is twice its width.if the height of the room is 11m,then the area of its ceiling is

Answer 1

Hey.

Here is the answer.

Total area of walls = 660 m^2

Height = 11m

Total area of walls = 2(L × h )+2(b × h)

as, L = 2b

so, total area = 2(2b × h) + 2(b × h)

= 4bh +2 bh = 6 bh = 660 m

or, 6bh = 660 m

or , 6b(11) = 660 m

or, b = 10 m

so, L = 2b = 20 m

So , area of celling is Lb = 20×10 = 200 m^2

Thanks.

Answer 2

Area of four walls = 2(l+b) ×height

Here,

Width = breadth = x
Length = 2x

===================

Area = 2(2x + x) × 11

660 = 2×11×(3x)

660/22 = 3x

30 = 3x

30/3 =x

10 = x

×××××××××××××××××××××××

Width = x = 10 m
Length = 2x = 2(10) = 20 m


Area of ceiling = length×breadth =10×20=200m²



I hope this will help you

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