The difference between 18 and 13 is: 
The difference between 79 and 76 is: 
The difference between 14 and 13 is: 
The difference between 18 and 11 is: 
The difference between 88 and 13 is: 
The difference between 18 and 13 is: 
The difference between 20 and 15 is: 
The difference between 18 and 13 is: 