Final answer:
To calculate the retail price r of an item that is on sale for $65 after a 15% discount, we identify that $65 represents 85% of the original price. By setting up the equation $65 = r x 0.85 and solving for r, we find that the retail price r is approximately $76.47.
Step-by-step explanation:
To find the retail price r before the discount, we can use the sale price information given and the percent discount to work backwards. The item on sale is $65 after a 15% discount. This means $65 is 85% (100% - 15%) of the original price.
Let's set up the equation using the percent in decimal form:
- Convert the percentage to a decimal by dividing by 100, which gives us 0.85.
- Set up the equation: Sale Price = Retail Price (1 - Discount Rate).
- Plug in the values: $65 = r × 0.85.
- Solve for r (retail price) by dividing both sides of the equation by 0.85.
- The calculation will be $65 / 0.85 = $76.47.
- The retail price r is approximately $76.47 before the discount.