Question

The number of marble slabs of size 25 cm x 25 cm required to pave the floor of a square room of side 10 metres is :

• A. 1600
• B. 1000
• C. 2000
• D. 2500

Answer 1

Answer:

A. 1600

1. Convert the room side from metres to centimetres:
   $1\text{ metre} = 100\text{ cm}$

2. $\text{Side of the square room} = 10\text{ m} = 10 \times 100 = 1,000\text{ cm}$

3. Calculate the area of the room floor:
   $\text{Area of the floor} = \text{Side} \times \text{Side} = 1,000\text{ cm} \times 1,000\text{ cm} = 1,000,000\text{ cm}^2$

4. Calculate the area of one marble slab:
   $\text{Area of one slab} = 25\text{ cm} \times 25\text{ cm} = 625\text{ cm}^2$

5. Calculate the total number of slabs required:
   $\text{Number of slabs} = \frac{\text{Area of the floor}}{\text{Area of one slab}}$

6. $\text{Number of slabs} = \frac{1,000 \times 1,000}{25 \times 25} = 40 \times 40 = \mathbf{1,600}$