For this case, the first thing we must do is define a variable. 
 We have then: 
 x: number of incorrect answers. 
 We now write the equation that models the number of incorrect questions. 
 We have then: 
 

 

 

 Answer: 
 a division sentence using negative numbers where the quotient represents the number of questions Fred answered incorrectly is: 
 

 the number of questions Fred answered incorrectly is:
 
