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.
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Question: Megan was selling her necklaces at a garage sale . She sold 7 bead necklaces and 3 gem stone necklaces . If each necklace cost 9 dollars , how much money did she earn ?

Answer: 90


Question: There school 's baseball team had 31 new players and 4 returning players . If the coach put them into groups with 7 players in each group , how many groups would there be ?

Answer: 5


Question: A new building needed 9 windows . The builder had already installed 6 of them . If it takes 6 hours to install each window , how long will it take him to install the rest ?

Answer:
18