You are given a math word problem and you are supposed to apply a single mathematical operator like addition, subtraction, multiplication, or division 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: a fast food restaurant had 91 hotdogs . after selling some they had 20 left . what 's the difference between the number of hotdogs before selling and after selling ?

Answer: 71

Question: gino has 63 popsicle sticks . i have 50 popsicle sticks . what is the sum of our popsicle sticks ?

Answer: 113

Question: victor had $ 10 . for his allowance he got another $ 8 . how much money does he have total ?

Answer:
18