The difference between 98 and 78 is: 
The difference between 91 and 13 is: 
The difference between 99 and 78 is: 
The difference between 98 and 76 is: 
The difference between 98 and 78 is: 
The difference between 98 and 18 is: 
The difference between 91 and 77 is: 
The difference between 98 and 78 is: 