The difference between 80 and 21 is: 
The difference between 31 and 29 is: 
The difference between 86 and 21 is: 
The difference between 80 and 20 is: 
The difference between 80 and 21 is: 
The difference between 80 and 61 is: 
The difference between 89 and 20 is: 
The difference between 80 and 21 is: 