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 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

Answer: e


Question: Problem: an investor deposited $ 10,000 to open a new savings account that earned 12 percent annual interest, compounded quarterly. if there were no other transactions in the account, what was the amount of money in the account 6 months after the account was opened ?
Options: a. $ 10,300, b. $ 10,303, c. $ 10,600, d. $ 10,609, e. $ 10,900

Answer: d


Question: Problem: a man buys an article for $ 100. and sells it for $ 130. find the gain percent ?
Options: a. 10 %, b. 15 %, c. 25 %, d. 20 %, e. 30 %

Answer:
e