The difference between 60 and 60 is: 
The difference between 33 and 13 is: 
The difference between 64 and 60 is: 
The difference between 60 and 60 is: 
The difference between 80 and 60 is: 
The difference between 60 and 40 is: 
The difference between 61 and 63 is: 
The difference between 60 and 60 is: 