The difference between 81 and 51 is: 
The difference between 88 and 16 is: 
The difference between 84 and 51 is: 
The difference between 81 and 50 is: 
The difference between 71 and 51 is: 
The difference between 81 and 71 is: 
The difference between 80 and 51 is: 
The difference between 81 and 51 is: 