The difference between 64 and 18 is: 
The difference between 87 and 66 is: 
The difference between 69 and 18 is: 
The difference between 64 and 10 is: 
The difference between 54 and 18 is: 
The difference between 64 and 18 is: 
The difference between 67 and 11 is: 
The difference between 64 and 18 is: 