The difference between 60 and 15 is: 
The difference between 52 and 21 is: 
The difference between 66 and 15 is: 
The difference between 60 and 10 is: 
The difference between 60 and 15 is: 
The difference between 60 and 45 is: 
The difference between 68 and 13 is: 
The difference between 60 and 15 is: 