The difference between 31 and 19 is: 
The difference between 79 and 70 is: 
The difference between 39 and 19 is: 
The difference between 31 and 10 is: 
The difference between 41 and 19 is: 
The difference between 31 and 29 is: 
The difference between 37 and 15 is: 
The difference between 31 and 19 is: 