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

Q: A textbook costs a bookstore 44 dollars , and the store sells it for 55 dollars . Find the amount of profit based on the selling price .

A: 11
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Q: Tom was putting his spare change into piles . He had 2 piles of quarters and 4 piles of dimes . If each pile had 5 coins in it , how many coins did he have total ?

A: 30
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Q: Oliver was organizing his baseball cards in a binder with 3 on each page . If he had 2 new cards and 10 old cards to put in the binder , how many pages would he use ?

A:
4
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