The difference between 16 and 13 is: 
The difference between 25 and 23 is: 
The difference between 19 and 13 is: 
The difference between 16 and 13 is: 
The difference between 26 and 13 is: 
The difference between 16 and 13 is: 
The difference between 20 and 17 is: 
The difference between 16 and 13 is: 