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

Q: Melanie picked 7 plums and 4 oranges from the orchard . She gave 3 plums to Sam . How many plums does she have now ?

A: 4
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Q: 231 birds were sitting in a tree . Some more fly up to the tree . Then there were 312 birds in the tree . How many more fly up to the tree ?

A: 81
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Q: Benny has 6 blue marbles . Keith has 5 times more blue marbles than Benny . How many blue marbles does Keith have ?

A:
30
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