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: when 242 is divided by a certain divisor the remainder obtained is 15. when 698 is divided by the same divisor the remainder obtained is 27. however, when the sum of the two numbers 242 and 698 is divided by the divisor, the remainder obtained is 5. what is the value of the divisor ?
Options: a. 11, b. 17, c. 13, d. 23, e. 37

Answer: e


Question: Problem: the price of a certain painting increased by 30 % during the first year and decreased by 15 % during the second year. the price of the painting at the end of the 2 - year period was what percent of the original price ?
Options: a. 102 %, b. 105 %, c. 110.5 %, d. 112.5 %, e. 100 %

Answer: c


Question: Problem: one gear of pulley rotates at a speed of 3 rev / sec another gear roates at 5 rev / sec. if both start together after how many seconds will they be together again
Options: a. 3 sec, b. 5 sec, c. 15 sec, d. 20 sec, e. 25 sec

Answer:
c