You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: On an order of 5 dozen boxes of a consumer product, a retailer receives an extra dozen free. This is equivalent to allowing him a discount of:

Option A: 15%

Option B: 16 1/6%

Option C: 16 2/3%

Option D: 20%

Option E: 30%

A: Option C
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Q: Question: There are 36 students in a certain geometry class. If one third of the students are boys and one fourth of the boys are under six feet tall, how many boys in the class are under six feet tall?

Option A: 3

Option B: 12

Option C: 18

Option D: 24

Option E: 27

A: Option A
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Q: Question: In the new budget the price of milk rose by 20%. By how much percent must a person reduce his consumption so that his expenditure on it does not increase?

Option A: 7.5%

Option B: 9.1%

Option C: 10.9%

Option D: 16.67%

Option E: 15%

A:
Option D
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