The difference between 16 and 12 is: 
The difference between 49 and 18 is: 
The difference between 19 and 12 is: 
The difference between 16 and 11 is: 
The difference between 66 and 12 is: 
The difference between 16 and 12 is: 
The difference between 21 and 17 is: 
The difference between 16 and 12 is: 