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: what sum of money will produce rs. 80 as simple interest in 4 years at 3 1 / 2 percent ?
Options: a. 263, b. 571.4, c. 367, d. 368, e. 339

A: b
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Q: Problem: a 340 - liter solution of kola is made from 88 % water, 5 % concentrated kola and the rest is made from sugar. if 3.2 liters of sugar, 10 liter of water and 6.8 liters of concentrated kola were added to the solution, what percent of the solution is made from sugar ?
Options: a. 6 %., b. 7.5 %., c. 9.2 %., d. 10.5 %., e. 11 %.

A: b
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Q: Problem: the average age of 15 students of a class is 15 years. out of these, the average age of 8 students is 14 years and that of the other 6 students is 16 years, the age of the 15 th student is
Options: a. 17, b. 12, c. 13, d. 14, e. 15

A:
a
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