You are given a math word problem and you are supposed to only use subtraction on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Context: There were 8 people on the bus. At the next stop 12 more people got on the bus and 3 people got off. 

 Question: How many people are there on the bus now?
17

Context: Paco had 28 cookies. He ate some of them and had 7 cookies left. 

 Question: How many cookies did Paco eat?
21

Context: There were 53 dollars in Olivia's wallet. She collected 91 more dollars from an atm. After she visited a supermarket there were 14 dollars left. 

 Question: How much more money did she spend at the supermarket than she collected at the atm?

39