The difference between 90 and 89 is: 
The difference between 61 and 27 is: 
The difference between 99 and 89 is: 
The difference between 90 and 80 is: 
The difference between 90 and 89 is: 
The difference between 90 and 49 is: 
The difference between 97 and 86 is: 
The difference between 90 and 89 is: 