The difference between 91 and 78 is: 
The difference between 58 and 38 is: 
The difference between 99 and 78 is: 
The difference between 91 and 70 is: 
The difference between 81 and 78 is: 
The difference between 91 and 68 is: 
The difference between 94 and 71 is: 
The difference between 91 and 78 is: 