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.
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Question: Context: Some children were riding on the bus. At the bus stop 2 more children got on the bus. Then there were 41 children altogether on the bus. 

 Question: How many children were riding on the bus before the bus stop?

Answer: 39


Question: Context: Julia played tag with 15 kids on monday, 18 kids on tuesday and 7 kids on wednesday. 

 Question: How many more kids did she play with on monday and tuesday than on wednesday?

Answer: 26


Question: Context: Zachary did 15 push-ups in gym class today. David did 39 more push-ups than Zachary. John did 9 push-ups less than David. 

 Question: How many more push-ups did Zachary do than John?

Answer:
30