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: Ned had to wash 9 short sleeve shirts and 21 long sleeve shirts before school . If he had only washed 29 of them by the time school started , how many did he not wash ?

A: 1
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Q: Cody bought 7 boxes of chocolate candy and 3 boxes of caramel candy . If each box has 8 pieces inside it , how much candy did he have total ?

A: 80
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Q: A neighborhood grocer sells a mix of chocolate and carob candy . The chocolate cost 2.7 dollars a pound and the carob costs 2.55 dollars a pound . If 20 pounds of the chocolate and 40 pounds of the carob candy are used , what is the cost per pound of the mixture in dollars ?

A:
2.6
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