The difference between 36 and 29 is: 
The difference between 40 and 20 is: 
The difference between 39 and 29 is: 
The difference between 36 and 21 is: 
The difference between 36 and 29 is: 
The difference between 36 and 19 is: 
The difference between 38 and 21 is: 
The difference between 36 and 29 is: 