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.

Q: Context: There are 8 different movies and 21 different books in the ' crazy silly school ' series. If you read 7 of the books and watched 4 of the movies 

 Question: How many more movies do you still have to watch?

A: 4
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Q: Context: 36 children were riding on the bus. At the bus stop 68 children got off the bus while some more got on the bus. Then there were 12 children altogether on the bus. 

 Question: How many more children got off the bus than those that got on?

A: 24
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Q: Context: There were 3 dollars in Olivia's wallet. She collected 49 more dollars from an atm. After she visited a supermarket there were 49 dollars left. 

 Question: How much more money did she collect at the atm than she spent at the supermarket?

A:
46
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