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: Tom has 30 violet balloons , he gave Fred 16 of the balloons . How many violet balloons does he now have ?

A: 14
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Q: At the schools book fair Sam bought 13 adventure books and 17 mystery books . If 15 of the books were used , how many new books did he buy ?

A: 15
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Q: Diane has 37 crayons . She gets 5 more from Frances . Later , Diane buys 16 cards at the store . How many crayons does Diane have in all ?

A:
42
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