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 bag contains 12 red marbles. if someone were to remove 2 marbles from the bag, one at a time, and replace the first marble after it was removed, the probability that neither marble would be red is 25 / 36. how many marbles are in the bag ?
Options: a. 24, b. 48, c. 60, d. 72, e. 84

A: b
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Q: Problem: list r contains 5 numbers that have an average value of 60. if the median of the numbers in the list is equal to the mean and the largest number is equal to 20 more than two times the smallest number, what is the smallest possible value in the list ?
Options: a. 25, b. 28, c. 31, d. 34, e. 37

A: b
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Q: Problem: convert 0.32 in to a vulgar fraction ?
Options: a. 8 / 25, b. 16 / 50, c. 17 / 50, d. 19 / 50, e. none

A:
a
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