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.

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

Problem: ravi purchased a refrigerator and a mobile phone for rs. 15000 and rs. 8000 respectively. he sold the refrigerator at a loss of 5 percent and the mobile phone at a profit of 10 percent. overall he make a.
Options: a. 50, b. 288, c. 27, d. 200, e. 881
a

Problem: if all 6 are replaced by 9, the algebric sum of all numbers from 1 to 100 ( both inclusive. varies by ,
Options: a. 980, b. 330, c. 660, d. 990, e. 300

b