A hall is 12 m long and 5 m wide . If the height of the hall is 10 m , then find the surface area of the walls of the hall .

Answer

To find the surface area of the walls of the hall, we will follow these steps:

### Step 1: Identify the dimensions of the hall
- Length (L) = 12 m
- Width (W) = 5 m
- Height (H) = 10 m

### Step 2: Calculate the area of the two longer walls
The area of one longer wall (which has a length of 12 m and height of 10 m) is calculated as:
\[ \text{Area of one longer wall} = \text{Length} \times \text{Height} = 12 \, \text{m} \times 10 \, \text{m} = 120 \, \text{m}^2 \]
Since there are two longer walls, the total area for both is:
\[ \text{Total area of longer walls} = 2 \times 120 \, \text{m}^2 = 240 \, \text{m}^2 \]

### Step 3: Calculate the area of the two shorter walls
The area of one shorter wall (which has a width of 5 m and height of 10 m) is calculated as:
\[ \text{Area of one shorter wall} = \text{Width} \times \text{Height} = 5 \, \text{m} \times 10 \, \text{m} = 50 \, \text{m}^2 \]
Since there are two shorter walls, the total area for both is:
\[ \text{Total area of shorter walls} = 2 \times 50 \, \text{m}^2 = 100 \, \text{m}^2 \]

### Step 4: Calculate the total surface area of the walls
Now, we add the total areas of the longer walls and the shorter walls:
\[ \text{Total surface area of walls} = \text{Total area of longer walls} + \text{Total area of shorter walls} \]
\[ \text{Total surface area of walls} = 240 \, \text{m}^2 + 100 \, \text{m}^2 = 340 \, \text{m}^2 \]

### Final Answer
The surface area of the walls of the hall is \(340 \, \text{m}^2\).

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