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: There are 97 erasers in a box . Ernest has 17 erasers in a bag . Mark takes 97 erasers out of the box . How many erasers are left in the box ?

A: 0
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Q: Harry Hound had a terrible earache yesterday . When I peered into his ears yesterday , I found 36 frisky fleas having a party in his right ear and 85 baby fleas sleeping peacefully in his left ear . I cleaned out Harry Hound 's ears . How many fleas perished ?

A: 121
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Q: 2 birds were sitting on the fence . 4 more birds came to join them . How many birds are sitting on the fence ?

A:
6
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