The difference between 91 and 39 is: 
The difference between 89 and 35 is: 
The difference between 99 and 39 is: 
The difference between 91 and 30 is: 
The difference between 61 and 39 is: 
The difference between 91 and 29 is: 
The difference between 93 and 31 is: 
The difference between 91 and 39 is: 