1. The problem states that lemons cost $n$ cents each and the total cost of a box of lemons is $L$ cents. 2. We want to find a formula for the cost of a box of lemons when each lemon costs 10 cents. 3. The cost of a box of lemons is given by the formula $$L = n \times \text{number of lemons}$$ where $n$ is the cost per lemon. 4. To find the number of lemons in the box, rearrange the formula: $$\text{number of lemons} = \frac{L}{n}$$ 5. When lemons cost 10 cents each, the cost of the box is $$L_{10} = 10 \times \text{number of lemons}$$ 6. Substitute the number of lemons from step 4 into this formula: $$L_{10} = 10 \times \frac{L}{n}$$ 7. This formula gives the cost of the box when lemons cost 10 cents each. **Final formula:** $$L_{10} = \frac{10L}{n}$$