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: Find the average of all prime numbers between 4 and 15.

 Option A: 30

 Option B: 4

 Option C: 9

 Option D: 8

 Option E: None

A: Option C
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Q: Question: A can run 192 metre in 28 seconds and B in 32 seconds. By what distance A beat B?

 Option A: 38 metre

 Option B: 28 metre

 Option C: 24 metre

 Option D: 15 metre

 Option E: 28 metre

A: Option C
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Q: Question: If 6 (A's capital) = 8 (B's capital) = 10 (C's capital). Then the ratio of their capitals is?

 Option A: 20:15:16

 Option B: 20:15:68

 Option C: 20:15:12

 Option D: 20:15:11

 Option E: 20:15:19

A:
Option C
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