Question

The area of the four walls of a room is 120 m2
. The length is twice the breadth. If height of a room is 4 m, find the breadth

Answer 1

Answer:

Let the breadth of room be x m.

then , length of room=2x m.

Area of four walls of room=2 (l+b)*h .

120=2 (x+2x)*4 .

120/4=2x+4x .

6x=30 .

x=5 .

Thus, The breadth of room is 5m .

Answer 2

Answer :

• Area of floor is 50m²
• breadth is 5m

Given :

• The area of the four walls of a room is 120m²
• The length is twice the breadth
• Hejght is 4m

To find :

• Breadth

Solution :

• Let the breadth of wall be x

Given That , The length is twice the breadth then,

• Let the length of wall be 2x
• Height is 4m

As we know that,

• Area of 4 walls = 2(l+b)h

Area of four walls is 120m² then,

⇢ Area of 4 walls = 2(length + breadth)× height

where , area of 4 walls is 120m² , length is 2x , breadth is x and height is 4m

⇢ Area of four walls = 2(l + b)h

⇢ 120m = 2(2x + x)4

⇢ 120m = 8 × 3x

⇢ 120/8 = 3x

⇢ 15 = 3x

⇢ x = 15/3

⇢ x = 5

Hence , breadth is 5 m

• breadth is 5m
• length is 2x = 2(5) = 10m

Now ,

• Area of floor = length × breadth

⇢ 10 × 5

⇢ 50m²

Hence, Area of floor is 50m²