The difference between 81 and 16 is: 
The difference between 67 and 61 is: 
The difference between 88 and 16 is: 
The difference between 81 and 10 is: 
The difference between 81 and 16 is: 
The difference between 81 and 16 is: 
The difference between 86 and 11 is: 
The difference between 81 and 16 is: 