1. **State the problem:** We are given a table showing the weight in pounds and the corresponding price in dollars. We need to find the constant of proportionality, which is the price per pound. 2. **Understand the concept:** The constant of proportionality $k$ in a direct variation problem relates two variables by the formula: $$\text{Price} = k \times \text{Weight}$$ Here, $k$ represents the price per pound. 3. **Use the data:** From the table, when the weight is 1 lb, the price is 2.50 dollars. Using the formula: $$2.50 = k \times 1$$ 4. **Solve for $k$:** $$k = \frac{2.50}{1}$$ 5. **Simplify:** $$k = 2.50$$ 6. **Interpretation:** The constant of proportionality is 2.50 dollars per pound, meaning each pound costs 2.50 dollars. **Final answer:** The constant of proportionality is $2.50$ dollars per pound.