The difference between 90 and 80 is: 
The difference between 31 and 25 is: 
The difference between 99 and 80 is: 
The difference between 90 and 80 is: 
The difference between 90 and 80 is: 
The difference between 90 and 30 is: 
The difference between 90 and 82 is: 
The difference between 90 and 80 is: 