The number of bricks of size 20 cm by 10 cm needed to floor a room of size 20 m by 16 m is

Options

A. 200
B. 2000
C. 20000
D. 16000

Answer

To solve the problem of how many bricks of size 20 cm by 10 cm are needed to floor a room of size 20 m by 16 m, we will follow these steps:

### Step 1: Calculate the area of one brick.
The dimensions of the brick are given as:
- Length = 20 cm
- Width = 10 cm

The area of one brick can be calculated using the formula:
\[ \text{Area of one brick} = \text{Length} \times \text{Width} = 20 \, \text{cm} \times 10 \, \text{cm} = 200 \, \text{cm}^2 \]

### Step 2: Calculate the area of the room.
The dimensions of the room are given as:
- Length = 20 m
- Width = 16 m

First, we calculate the area in square meters:
\[ \text{Area of the room} = \text{Length} \times \text{Width} = 20 \, \text{m} \times 16 \, \text{m} = 320 \, \text{m}^2 \]

### Step 3: Convert the area of the room from square meters to square centimeters.
Since 1 m² = 10,000 cm², we convert the area:
\[ \text{Area of the room in cm}^2 = 320 \, \text{m}^2 \times 10,000 \, \text{cm}^2/\text{m}^2 = 3,200,000 \, \text{cm}^2 \]

### Step 4: Calculate the number of bricks needed.
To find the number of bricks required to cover the entire floor area, we divide the area of the room by the area of one brick:
\[ \text{Number of bricks} = \frac{\text{Area of the room}}{\text{Area of one brick}} = \frac{3,200,000 \, \text{cm}^2}{200 \, \text{cm}^2} = 16,000 \]

### Final Answer:
The number of bricks needed to floor the room is **16,000**.

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