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: how many prime numbers are between 76 / 8 and 124 / 5 ?
Options: a. 1, b. 2, c. 3, d. 4, e. 5

A: e
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Q: Problem: the average age of 17 persons in a office is 15 years. out of these, the average age of 5 of them is 14 years and that of the other 9 persons is 16 years. the age of the 15 th person is ?
Options: a. 39, b. 41, c. 45, d. 42, e. 50

A: b
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Q: Problem: there are 5 people who can build 5 houses in just 5 days. increase the amount of people to 100. how long would it take these 100 people to build 100 houses ?
Options: a. 2 days, b. 3 days, c. 4 days, d. 5 days, e. 1 days

A:
d
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