Find the number of bricks required to construct a wall of dimensions `3 m xx 1.5 m xx 0.4 m`, if the dimension of a brick is `30 cm xx 15 cm xx 8 cm`.

Answer

To find the number of bricks required to construct a wall with given dimensions, we will follow these steps:

### Step 1: Calculate the Volume of the Wall
The dimensions of the wall are given as:
- Length = 3 m
- Height = 1.5 m
- Thickness = 0.4 m

First, we need to convert these dimensions from meters to centimeters since the dimensions of the brick are in centimeters.

1 meter = 100 centimeters, so:
- Length in cm = 3 m × 100 = 300 cm
- Height in cm = 1.5 m × 100 = 150 cm
- Thickness in cm = 0.4 m × 100 = 40 cm

Now, we can calculate the volume of the wall:
\[ \text{Volume of the wall} = \text{Length} \times \text{Height} \times \text{Thickness} = 300 \, \text{cm} \times 150 \, \text{cm} \times 40 \, \text{cm} \]

Calculating this gives:
\[ \text{Volume of the wall} = 300 \times 150 \times 40 = 1,800,000 \, \text{cm}^3 \]

### Step 2: Calculate the Volume of One Brick
The dimensions of one brick are given as:
- Length = 30 cm
- Width = 15 cm
- Height = 8 cm

Now, we can calculate the volume of one brick:
\[ \text{Volume of one brick} = \text{Length} \times \text{Width} \times \text{Height} = 30 \, \text{cm} \times 15 \, \text{cm} \times 8 \, \text{cm} \]

Calculating this gives:
\[ \text{Volume of one brick} = 30 \times 15 \times 8 = 3600 \, \text{cm}^3 \]

### Step 3: Calculate the Number of Bricks Required
To find the number of bricks required, we divide the volume of the wall by the volume of one brick:
\[ \text{Number of bricks} = \frac{\text{Volume of the wall}}{\text{Volume of one brick}} = \frac{1,800,000 \, \text{cm}^3}{3600 \, \text{cm}^3} \]

Calculating this gives:
\[ \text{Number of bricks} = \frac{1,800,000}{3600} = 500 \]

### Final Answer
The number of bricks required to construct the wall is **500**.

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