You are given a math word problem and you are supposed to apply multiple mathematical operators 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.

Q: at lunch a waiter had 10 customers and 5 of them did n't leave a tip . if he got $ 3 each from the 1 who did tip how much money did he earn ?

A: 15
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Q: the book fair had a sale where 3 books were $ 18.72 . if you wanted to buy 6 books how much money would you need ?

A: 37.44
****
Q: lawrence has 5504 marbles . if he shares them among 64 friends how many marbles does each friend get ?

A:
86
****