1. **State the problem:** We want to find the best buy for peanut butter using a 40¢-off coupon that applies to different jar sizes and quantities. 2. **Given data:** - Prices: 12-oz jar = 2.85, 18-oz jar = 3.49, 28-oz jar = 5.15, 40-oz jar = 6.29 - Coupon: 40¢ off one 40-oz jar, or one 28-oz jar, or two 18-oz jars, or two 12-oz jars. 3. **Calculate total cost and cost per ounce for each option:** **Option 1: One 40-oz jar** - Jars needed = 1 - Cost per jar = 6.29 - Total cost = $6.29 - Cost with coupon = $6.29 - 0.40 = $5.89 - Total ounces = 40 - Cost per ounce = $$\frac{5.89}{40} = 0.14725$$ **Option 2: One 28-oz jar** - Jars needed = 1 - Cost per jar = 5.15 - Total cost = $5.15 - Cost with coupon = $5.15 - 0.40 = $4.75 - Total ounces = 28 - Cost per ounce = $$\frac{4.75}{28} \approx 0.16964$$ **Option 3: Two 18-oz jars** - Jars needed = 2 - Cost per jar = 3.49 - Total cost = $3.49 \times 2 = 6.98 - Cost with coupon = $6.98 - 0.40 = $6.58 - Total ounces = 18 \times 2 = 36 - Cost per ounce = $$\frac{6.58}{36} \approx 0.18278$$ **Option 4: Two 12-oz jars** - Jars needed = 2 - Cost per jar = 2.85 - Total cost = $2.85 \times 2 = 5.70 - Cost with coupon = $5.70 - 0.40 = $5.30 - Total ounces = 12 \times 2 = 24 - Cost per ounce = $$\frac{5.30}{24} \approx 0.22083$$ 4. **Compare cost per ounce:** - 40-oz jar: 0.14725 - 28-oz jar: 0.16964 - Two 18-oz jars: 0.18278 - Two 12-oz jars: 0.22083 5. **Conclusion:** The best buy is the 40-oz jar with coupon, as it has the lowest cost per ounce. **Final answer:** Buy one 40-oz jar with the coupon for the best value.