Find the area of four walls of a room whose length is 6 m, breadth is 5 m and heigth is 4 m.

Answer

To find the area of the four walls of a room, we can use the formula for the curved surface area of a cuboid. The room can be considered as a cuboid where the length, breadth, and height are given.

### Step-by-step Solution:

1. **Identify the dimensions of the room:**
- Length (L) = 6 m
- Breadth (B) = 5 m
- Height (H) = 4 m

2. **Understand the formula for the area of the four walls:**
The area of the four walls of a cuboid can be calculated using the formula:
\[ \text{Area of four walls} = 2H(L + B) \]
where H is the height, L is the length, and B is the breadth.

3. **Substitute the values into the formula:**
- Substitute H = 4 m, L = 6 m, and B = 5 m into the formula:
\[ \text{Area of four walls} = 2 \times 4 \times (6 + 5) \]

4. **Calculate the sum of length and breadth:**
- Calculate \(6 + 5\):
\[ 6 + 5 = 11 \]

5. **Multiply the values:**
- Now substitute back into the formula:
\[ \text{Area of four walls} = 2 \times 4 \times 11 \]
- Calculate \(2 \times 4 = 8\):
\[ \text{Area of four walls} = 8 \times 11 \]

6. **Final calculation:**
- Now calculate \(8 \times 11\):
\[ \text{Area of four walls} = 88 \, \text{m}^2 \]

### Conclusion:
The area of the four walls of the room is **88 m²**.