The difference between 90 and 49 is: 
The difference between 58 and 28 is: 
The difference between 99 and 49 is: 
The difference between 90 and 40 is: 
The difference between 90 and 49 is: 
The difference between 90 and 29 is: 
The difference between 94 and 43 is: 
The difference between 90 and 49 is: 