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: What does the hexa number E78 in radix 7.

 Option A: 12455

 Option B: 14153

 Option C: 14256

 Option D: 13541

 Option E: 14541

A: Option D
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Q: Question: Anthony and Michael sit on the six member board of directors for company X. If the board is to be split up into 2 three-person subcommittees, what percent R of all the possible subcommittees that include Michael also include Anthony?

 Option A:  20%

 Option B:  30%

 Option C:  40%

 Option D:  50%

 Option E:  60%

A: Option C
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Q: Question: Two pipes function simultaneously the reservoir will be filled in 12 hours. One pipe fills reservoir 10 hours faster than the other. How many hours does the faster pipe take to fill the reservoir?

 Option A: 33

 Option B: 88

 Option C: 20

 Option D: 72

 Option E: 27

A:
Option C
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