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: John weighs 81 pounds . Roy weighs 4 pounds . How much heavier is John than Roy ?

A: 77
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Q: 532 people are watching a movie in a theater . The theater has 750 seats . How many seats are empty in the theater ?

A: 218
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Q: The school cafeteria ordered 6 red apples and 15 green apples for students lunches . But , if only 5 students wanted fruit , how many extra did the cafeteria end up with ?

A:
16
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