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 12 potatoes . He has already cooked 6 . If each potato takes 6 minutes to cook , how long will it take him to cook the rest ?

Answer: 36

Question: Kaleb started his own lawn mowing business . In the spring he made 4 dollars mowing lawns and in the summer he made 50 dollars . If he had to spend 4 dollars buying supplies , how much money did he end up with ?

Answer: 50

Question: A store had 27 coloring books in stock . They ended up putting them on sale and getting rid of 6 of them . The put the ones they still had onto shelves with 7 on each shelf . How many shelves did they use ?

Answer:
3