1. **State the problem:** Mario bought four headphone sets and sold them for €320. The exchange rate is £1 = €1.1701. We need to find the profit Mario made and express it as a percentage of the total amount he spent. 2. **Calculate how much Mario paid in euros for the four headphone sets:** Given £59 per headphone set, for four sets: $$59 \times 4 = 236 \text{ pounds}$$ Convert to euros using the exchange rate: $$236 \times 1.1701 = 276.14 \text{ euros}$$ 3. **Calculate the profit Mario made:** Profit = Selling price - Cost price $$320 - 276.14 = 43.86 \text{ euros}$$ 4. **Express the profit as a percentage of the total amount spent:** Use the formula: $$\text{Profit percentage} = \frac{\text{Profit}}{\text{Cost price}} \times 100$$ Substitute values: $$\frac{43.86}{276.14} \times 100 = 15.9\%$$ **Final answers:** - Mario paid €276.14 for the four headphone sets. - He made a profit of €43.86. - The profit percentage is 15.9%.