The difference between 49 and 21 is: 
The difference between 63 and 18 is: 
The difference between 47 and 21 is: 
The difference between 49 and 28 is: 
The difference between 39 and 21 is: 
The difference between 49 and 11 is: 
The difference between 52 and 24 is: 
The difference between 49 and 21 is: 