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: cereal a is 10 % sugar by weight, whereas healthier but less delicious cereal b is 2 % sugar by weight. to make a delicious and healthy mixture that is 3 % sugar, what should be the ratio of cereal a to cereal b, by weight ?
Options: a. 2: 9, b. 2: 7, c. 1: 7, d. 1: 4, e. 1: 3

A: c
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Q: Problem: 40 is subtracted from 60 % of a number, the result is 50. find the number ?
Options: a. 150, b. 330, c. 277, d. 279, e. 712

A: a
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Q: Problem: a rectangular photograph is surrounded by a border that is 3 inch wide on each side. the total area of the photograph and the border is m square inches. if the border had been 6 inches wide on each side, the total area would have been ( m + 178 ) square inches. what is the perimeter of the photograph, in inches ?
Options: a. 34, b. 36, c. 38, d. 40, e. 20

A:
e
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