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.
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Question: Problem: a can do a job in 15 days and b in 20 days. if they work on it together for 4 days, then the fraction of the work that is left is ?
Options: a. 2 / 15, b. 8 / 15, c. 3 / 11, d. 1 / 12, e. 6 / 13

Answer: b


Question: Problem: if a / b = 1 / 3, b / c = 2, c / d = 1 / 2, d / e = 3 and e / f = 1 / 10, then what is the value of abc / def ?
Options: a. 27 / 4, b. 27 / 8, c. 3 / 4, d. 3 / 20, e. 1 / 4

Answer: d


Question: Problem: following an increase in prices, the price of a candy box was 20 pounds and the price of a can of soda was 6 pounds. if the price of a candy box was raised by 25 %, and the price of a can of soda was raised by 50 %. what was the price of a box of candy plus a can of soda before prices were raised ?
Options: a. 11., b. 20., c. 13., d. 14., e. 14.5

Answer:
b