The difference between 91 and 77 is: 
The difference between 90 and 17 is: 
The difference between 98 and 77 is: 
The difference between 91 and 70 is: 
The difference between 91 and 77 is: 
The difference between 91 and 47 is: 
The difference between 96 and 72 is: 
The difference between 91 and 77 is: 