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: A board of length L feet is cut into two pieces such that the length of piece A is 4 feet less than three times the length of piece B. Which of the following is the length, in feet, of piece A?

 Option A: (L+4

 Option B: (L-4

 Option C: (3L-4

 Option D: (3L-1

 Option E: (3L+4

A: Option C
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Q: Question: If the charge of staying in a student youth hostel $18.00/day for the first week, and $15.00/day for each additional week, How much does it cost to stay for 23 days?

 Option A: $336

 Option B: $289

 Option C: $282

 Option D: $274

 Option E: $286

A: Option A
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Q: Question: A factory has a fixed cost of $50,000 a month, and a cost of $2.5 for every item produced. If the selling price of a single item is $5, what is the number of items must be sold monthly for the factory to cover its cost exactly?

 Option A: 9,000

 Option B: 14,000

 Option C: 18,000

 Option D: 20,000

 Option E: 27,000

A:
Option D
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