1. **State the problem:** James bought 15 shirts, each costing 160. He spent a total amount of money that could also buy 20 identical backpacks. We need to find the cost of one backpack. 2. **Formula and rules:** Total money spent on shirts = Number of shirts $ \times $ Cost per shirt. Total money spent on backpacks = Number of backpacks $ \times $ Cost per backpack. Since the total money is the same, we set these equal: $$15 \times 160 = 20 \times \text{Cost per backpack}$$ 3. **Intermediate work:** Calculate total money spent on shirts: $$15 \times 160 = 2400$$ Set equal to backpacks total cost: $$2400 = 20 \times \text{Cost per backpack}$$ Divide both sides by 20 to isolate cost per backpack: $$\frac{2400}{\cancel{20}} = \frac{20 \times \text{Cost per backpack}}{\cancel{20}}$$ $$120 = \text{Cost per backpack}$$ 4. **Answer:** The cost of one backpack is **120**. This means each backpack costs 120, given the total money spent is the same as for the shirts.