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: in a factory, an average of 60 tv ' s are produced per day for the fist 25 days of the months. a few workers fell ill for the next 5 days reducing the daily avg for the month to 58 sets / day. the average production per day for day last 5 days is ?
Options: a. 20, b. 36, c. 48, d. 50, e. 59

A: c
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Q: Problem: the population of a town increases 25 % and 40 % respectively in two consecutive years. after the growth the present population of the town is 1750. then what is the population of the town 2 years ago ?
Options: a. a. 750, b. b. 800, c. c. 850, d. d. 900, e. e. 950

A: b
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Q: Problem: pipe a fills a tank of capacity 800 liters at the rate of 40 liters a minute. another pipe b fills the same tank at the rate of 30 liters a minute. a pipe at the bottom of the tank drains the tank at the rate of 20 liters a minute. if pipe a is kept open for a minute and then closed and pipe b is open for a minute and then closed and then pipe c is open for a minute and then closed and the cycle is repeated, when will the tank be full ?
Options: a. 48 minutes, b. 14 minutes, c. 39 minutes, d. 40 minutes 20 seconds, e. none of these

A:
a
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