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: 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


[Q]: Problem: the perimeter of an isosceles right triangle is 12 + 12 sq rt 2. what is the length of the hypotenuse of the triangle ?
Options: ['a. 5', 'b. 6', 'c. 7', 'd. 8.485', 'e. 8']
[A]: d


[Q]: Problem: a sum of money is distributed among w, x, y, z in the proportion of 4: 2: 5: 3. if y gets $ 500 more than z, what is the x ' s share ?
Options: a. $ 4000, b. $ 500, c. $ 2500, d. $ 2800, e. $ 1400
[A]:
b