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: The greatest number that divides 180, 565 and 705 leaving remainder 5, 5 and 5 respectively is:

 Option A: 31

 Option B: 33

 Option C: 35

 Option D: 38

 Option E: 39

A: Option C
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Q: Question: A code is to be made by arranging 9 letters. five of the letters used will be the letter A, two of the letters used will be the letter B, one of the letters used will be the letter C, and one of the letters used will be the letter D. If there is only one way to present each letter, how many different codes are possible?

 Option A: 42

 Option B: 210

 Option C: 46820

 Option D: 84002

 Option E: 90720

A: Option E
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Q: Question: If x + y = 8 and y − 3x = 7, then what is the value of y-x?

 Option A: 1/7

 Option B: 3

 Option C: 15

 Option D: 15/2

 Option E: 60/7

A:
Option D
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