______ squares of each side 1 m makes a square of side 5 km.

Answer

To solve the problem of how many squares of each side 1 meter are needed to make a square of side 5 km, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the dimensions**:
- We have a large square with a side length of 5 km.
- We have small squares with a side length of 1 m.

2. **Convert the dimensions to the same unit**:
- Since the small squares are in meters, we need to convert the side of the large square from kilometers to meters.
- 1 km = 1000 m, so 5 km = 5 × 1000 m = 5000 m.

3. **Calculate the area of the large square**:
- The area \( A \) of a square is given by the formula \( A = \text{side} \times \text{side} \).
- For the large square:
\[ A_{\text{large}} = 5000 \, \text{m} \times 5000 \, \text{m} = 25,000,000 \, \text{m}^2. \]

4. **Calculate the area of the small square**:
- The area of the small square is:
\[ A_{\text{small}} = 1 \, \text{m} \times 1 \, \text{m} = 1 \, \text{m}^2. \]

5. **Determine how many small squares fit into the large square**:
- To find the number of small squares needed to cover the area of the large square, we divide the area of the large square by the area of one small square:
\[ x = \frac{A_{\text{large}}}{A_{\text{small}}} = \frac{25,000,000 \, \text{m}^2}{1 \, \text{m}^2} = 25,000,000. \]

6. **Express the answer in scientific notation**:
- The number of small squares can also be expressed as:
\[ x = 25 \times 10^6. \]

### Final Answer:
Therefore, the number of squares of each side 1 m needed to make a square of side 5 km is **25,000,000** or **25 × 10^6**.