Note: The height of the room must be 3 m instead of 3 cm because 3 cm is too small and it cannot be the height of a room.
Given:
Perimeter of the floor of a room = 18 metre
Height of the room = 3 metre
To find:
The area of 4 walls of the room.
Solution:
We know that, the area of 4 walls of the room is the curved surface area of the cuboid room.
The curved surface area of the cuboid is

Where, h is height, l is length and b is breadth.
Perimeter of the rectangular base is 2(l+b). So,

Putting the given values, we get


Therefore, the area of 4 walls of the room is 54 sq. metres.
Answer:
the last one(26 by 22) not sure whether its D or E but yah
Step-by-step explanation:
After having done this on paper:

We want to isolate the variable, and the first step is to subtract the 8.

Since the <em>n</em> is being multiplied by 3, and that = 8, we can multiply both sides by 3.
<em>n</em> = 24
Let me know if this helped you understand better.
Also, you can check this by substituting in 24 for <em>n</em>.