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.
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Question: Wendy was playing a video game and had 10 lives . In a hard part of the game she lost 6 lives . If she got 37 more lives in the next level , how many lives would she have ?

Answer: 41


Question: In fourth grade there were 4 students at the start of the year . During the year 3 students left and 42 new students came to school . How many students were in fourth grade at the end ?

Answer: 43


Question: 29 birds were sitting in a tree . Some more fly up to the tree . Then there were 42 birds in the tree . How many more flew up to the tree ?

Answer:
13