The difference between 60 and 51 is: 
The difference between 66 and 12 is: 
The difference between 68 and 51 is: 
The difference between 60 and 50 is: 
The difference between 60 and 51 is: 
The difference between 60 and 21 is: 
The difference between 69 and 50 is: 
The difference between 60 and 51 is: 