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: Bianca had 45 coloring books . If she gave away 6 of them , but then bought 20 more , how many would she have total ?

A: 59
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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: There are 37 short bushes and 30 tall trees currently in the park . Park workers will plant 20 short bushes today . How many short bushes will the park have when the workers are finished ?

A:
57
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