1. The problem asks to find the sale price of diapers originally costing 28.75 with a 10% markdown. 2. The formula for the sale price after a discount is: $$\text{Sale Price} = \text{Original Price} - (\text{Discount Rate} \times \text{Original Price})$$ 3. Substitute the given values: $$\text{Sale Price} = 28.75 - (0.10 \times 28.75)$$ 4. Calculate the discount amount: $$0.10 \times 28.75 = 2.875$$ 5. Subtract the discount from the original price: $$28.75 - 2.875 = 25.875$$ 6. Therefore, the sale price of the diapers is $25.875.