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: A chef needs to cook 9 potatoes . He has already cooked 7 . If each potato takes 3 minutes to cook , how long will it take him to cook the rest ?

Answer: 6


Question: At lunch a waiter had 7 customers and 4 of them did n't leave a tip . If he got $ 9 each from the ones who did tip , how much money did he earn ?

Answer: 27


Question: Vanessa and her mom were picking carrots from their garden . Vanessa picked 17 and her mother picked 14 . If only 24 of the carrots were good , how many bad carrots did they have ?

Answer:
7