1. **State the problem:** We need to find the discount percentage when the original price is $7 and the sale price is $3.57. 2. **Formula for discount percentage:** $$\text{Discount Percentage} = \frac{\text{Original Price} - \text{Sale Price}}{\text{Original Price}} \times 100\%$$ 3. **Calculate the discount amount:** $$7 - 3.57 = 3.43$$ 4. **Substitute values into the formula:** $$\text{Discount Percentage} = \frac{3.43}{7} \times 100\%$$ 5. **Simplify the fraction:** $$\frac{3.43}{7} = 0.49$$ 6. **Calculate the percentage:** $$0.49 \times 100\% = 49\%$$ **Final answer:** The discount is 49%.