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: a bag has 9 green balls and 23 pink balls. how many green balls should be added to the bag so that the ratio of green balls and pink balls in the bag becomes 1: 1 ?
Options: a. 10, b. 11, c. 12, d. 13, e. 14

A: e
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Q: Problem: if the sides of a cube are in the ratio 5: 3. what is the ratio of their diagonals ?
Options: ['a. 5: 9', 'b. 9: 3', 'c. 5: 4', 'd. 3: 5', 'e. 5: 3']

A: e
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Q: Problem: the average of 6 no. ' s is 4.60. the average of 2 of them is 3.4, while the average of the other 2 is 3.8. what is the average of the remaining 2 no ' s ?
Options: a. 2.3, b. 6.6, c. 3.6, d. 4.5, e. 4.6

A:
b
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