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: David did 51 push-ups in gym class today. David did 49 more push-ups than Zachary. 

 Question: How many push-ups did Zachary and David do altogether?

A: 53
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Q: Context: Katie had 57 new games and 39 old games. Her friends had 34 new games. 

 Question: How many more games does Katie have than her friends?

A: 62
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Q: Context: 28 children were riding on the bus. At the bus stop 82 children got on the bus while some got off the bus. Then there were 30 children altogether on the bus. 

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

A:
2
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