An online retail store charges a flat shipping fee of for any order, plus per pound of the package's weight. A customer places an order and uses a coupon that gives them a discount on the total cost (the flat shipping fee plus the weight cost). If the customer's total bill after the discount is , what would their total bill have been, in dollars, if they had not used the coupon?
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- Answer
Answer
The total bill without the coupon would have been .
The correct answer represents the total cost before the coupon discount. Since a discount was applied to the entire bill, the final bill of represents of the original total bill. Setting up the equation and dividing by yields the original total bill of .
Step-by-Step Solution
Key Concept
Translating percentage changes and linear cost models into algebraic equations.
Alternative Method
You can also solve this by finding the weight of the package first. Setting up the equation with the weight gives . Dividing by simplifies the expression to , which is the original bill. Solving further gives and pounds. Substituting back into the original cost formula yields .
Estimated Time:1m 30s