To solve this problem you must apply the proccedure shown below:
1. You have that you paid $80 for a tennis racket which was under a sign stating 1/4 off. Therefore, you can express this with the following equation:
[tex] x-x/4=80
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Where [tex]x[/tex]is the original retail price.
2. When you solve for [tex]x[/tex], you obtain:
[tex]3/4x=80 \\ x=106.67[/tex]
The answer is: [tex]106.67 dollars
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