You paid $80 for a tennis racket. if you found the racket under a sign stating 1/4 off, what must the original retail price have been?

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:
 
 Where is the original retail price.
 2. When you solve for , you obtain:
 
 The answer is: 

For a 0.25 pfor b o.3pp (0.25+0.3)=0.28