1. **Problem:** Translate "w is directly proportional to v" into an equation. 2. **Formula:** Direct variation means $w = kv$ where $k$ is the constant of proportionality. 3. **Explanation:** When one variable is directly proportional to another, as one increases, the other increases at a constant rate. 4. **Answer:** The equation is $$w = kv$$ where $k$ is a constant. This is the first problem from the worksheet.