The difference between 91 and 47 is: 
The difference between 97 and 20 is: 
The difference between 99 and 47 is: 
The difference between 91 and 40 is: 
The difference between 51 and 47 is: 
The difference between 91 and 17 is: 
The difference between 99 and 45 is: 
The difference between 91 and 47 is: 