Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Q: Problem: a person buys an article at $ 600. at what price should he sell the article so as to make a profit of 8 % ?
Options: a. 670, b. 689, c. 648, d. 740, e. 889

A: c
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Q: Problem: the average runs scored by a batsman in 30 matches is 50. in the next 15 matches the batsman scored an average of 26 runs. find his average in all the 45 matches ?
Options: a. 31, b. 42, c. 29, d. 97, e. 27

A: b
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Q: Problem: when x is multiplied by 3, the result is 10 more than the result of subtracting x from 26. what is the value of x ?
Options: a. - 4, b. 9, c. 11, d. 13, e. 22

A:
b
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