The difference between 91 and 79 is: 
The difference between 78 and 28 is: 
The difference between 99 and 79 is: 
The difference between 91 and 70 is: 
The difference between 91 and 79 is: 
The difference between 91 and 79 is: 
The difference between 93 and 71 is: 
The difference between 91 and 79 is: 