Represent the whole number 3,15 and 21 on a number line.

Answer

To represent the whole numbers 3, 15, and 21 on a number line, follow these steps:

### Step-by-Step Solution:

1. **Draw a Horizontal Line**: Start by drawing a straight horizontal line. This will be your number line.

2. **Mark the Center Point (Zero)**: Choose a point on the line to represent zero. This is the starting point of your number line.

3. **Label Positive Numbers**: From the zero point, mark equal intervals to the right for positive whole numbers. You can label them as follows:
- 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22.

4. **Locate and Mark the Number 3**: Find the number 3 on your number line. Place a point above the line at the position of 3 and label it as '3'.

5. **Locate and Mark the Number 15**: Next, find the number 15 on your number line. Place a point above the line at the position of 15 and label it as '15'.

6. **Locate and Mark the Number 21**: Finally, find the number 21 on your number line. Place a point above the line at the position of 21 and label it as '21'.

7. **Final Representation**: You should now have a number line with points marked for 3, 15, and 21.