The difference between 49 and 40 is: 
The difference between 70 and 15 is: 
The difference between 43 and 40 is: 
The difference between 49 and 40 is: 
The difference between 79 and 40 is: 
The difference between 49 and 30 is: 
The difference between 51 and 42 is: 
The difference between 49 and 40 is: 