Express the following numbers in dot patterns: 15

Answer

To express the number 15 in dot patterns, we can arrange the dots in a triangular formation. Here’s how to do it step by step:

### Step-by-Step Solution:

1. **Understand the Concept of Dot Patterns**:
- We will arrange the dots in rows, where each row contains one more dot than the previous row.

2. **Start with the First Row**:
- The first row will have 1 dot.
- **Row 1**: ●

3. **Add the Second Row**:
- The second row will have 2 dots.
- **Row 2**: ● ●

4. **Add the Third Row**:
- The third row will have 3 dots.
- **Row 3**: ● ● ●

5. **Add the Fourth Row**:
- The fourth row will have 4 dots.
- **Row 4**: ● ● ● ●

6. **Add the Fifth Row**:
- The fifth row will have 5 dots.
- **Row 5**: ● ● ● ● ●

7. **Count the Total Dots**:
- Now, we will count the total number of dots used in all the rows:
- Row 1: 1 dot
- Row 2: 2 dots
- Row 3: 3 dots
- Row 4: 4 dots
- Row 5: 5 dots
- Total = 1 + 2 + 3 + 4 + 5 = 15 dots.

8. **Visual Representation**:
- When arranged, the dots look like this:
```
●
● ●
● ● ●
● ● ● ●
● ● ● ● ●
```

### Final Answer:
The number 15 can be expressed in dot patterns as shown above, forming a triangular shape.

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