Question

The area of four walls of a room is 120 m2. If the length of the room is twice its breadth and the height is 4 m. Find the area of the floor.

Answer 1

area of four walls 120 m2.
i.e. 2(l+b)h=120 m2
where l=length b=breadth h=height
given, l=2b
h=4m
therefore, 2(l+b)h=120
or, 2(2b+b)4=120
or, 24b=120
or, b=5m
l=2×5=10m
and, area of floor=10×5=50 m2(ans)

Answer 2

Hi friend,

Let the breadth be x
Length is double so it will be 2x
Height=4m
Area of four walls(CSA)=120 m^2

Let's find the dimensions-:

120=2*4(x+2x)
120= 8(x+2x)
120=8x+16x
120=24x
120/24=x
x=5 m

Length=2*x=2*5=10m
Breadth=5 m

Area of floor=L*B
=10*5
=50m^2

Hope it helped you...................