Q: What is 20 minus 19? A: 
Q: What is 55 minus 47? A: 
Q: What is 29 minus 19? A: 
Q: What is 20 minus 10? A: 
Q: What is 90 minus 19? A: 
Q: What is 20 minus 19? A: 
Q: What is 28 minus 17? A: 
Q: What is 20 minus 19? A: 