The difference between 51 and 50 is: 
The difference between 59 and 17 is: 
The difference between 55 and 50 is: 
The difference between 51 and 50 is: 
The difference between 71 and 50 is: 
The difference between 51 and 40 is: 
The difference between 60 and 59 is: 
The difference between 51 and 50 is: 