Q: How much is 20 minus 19? A: 
Q: How much is 37 minus 11? A: 
Q: How much is 29 minus 19? A: 
Q: How much is 20 minus 10? A: 
Q: How much is 70 minus 19? A: 
Q: How much is 20 minus 19? A: 
Q: How much is 24 minus 13? A: 
Q: How much is 20 minus 19? A: 