1. **Problem:** A company produces product X at a unit cost of 10. Fixed costs are 450000, and each unit sells for 25. How many units must be sold to make a positive profit of 510000? 2. **Formula and explanation:** Profit = Total Revenue - Total Cost Total Revenue = Selling Price per unit \( \times \) Number of units sold \(x\) Total Cost = Fixed Cost + (Unit Cost \( \times \) Number of units sold) We want profit to be 510000, so: $$\text{Profit} = 25x - (450000 + 10x) = 510000$$ 3. **Solve for \(x\):** $$25x - 450000 - 10x = 510000$$ $$15x - 450000 = 510000$$ $$15x = 510000 + 450000$$ $$15x = 960000$$ $$x = \frac{960000}{15} = 64000$$ 4. **Interpretation:** The company must sell more than 64000 units to make a positive profit of 510000. --- **Final answer:** The company must sell at least **64000** units to achieve the desired profit.