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: 30 pens and 75 pencils were purchased for 750. if the average price of a pencil was 2.00, find the average price of a pen.
Options: a. 20, b. 11, c. 12, d. 13, e. 14

A: a
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Q: Problem: in a mayoral election, candidate x received 1 / 2 more votes than candidate y, and candidate y received 2 / 5 fewer votes than z. if z received 25000 votes how many votes did candidate x received ?
Options: a. 18000, b. 22500, c. 24000, d. 26000, e. 32000

A: b
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Q: Problem: a can complete the job in 5 hours and b can complete the same job in 3 hours. a works for 1 hour and then b joins and both complete the job. what fraction of the job did b complete
Options: a. 1 / 8, b. 3 / 10, c. 1 / 2, d. 5 / 6, e. 8 / 9

A:
a
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