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: Joan purchased a basketball game for $ 5.2 , and a racing game for $ 4.23 . How much did Joan spend on video games ?

Answer: 9.43


Question: There are 69 erasers in a box . Jane has 15 erasers in a bag . Doris takes 54 erasers out of the box . How many erasers are left in the box ?

Answer: 15


Question: 14 birds were sitting in a tree . 21 more birds flew up to the tree . How many birds were there altogether in the tree ?

Answer:
35