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: calculate the share of z, if rs. 3720 is divided among x, y and z in the ratio 7: 8: 11 ?
Options: a. 1564.1, b. 1214.1, c. 1574.1, d. 1271.1, e. 1044.1
c

Problem: kathleen can paint a room in 4 hours, and anthony can paint an identical room in 5 hours. how many hours would it take kathleen and anthony to paint both rooms if they work together at their respective rates ?
Options: a. 8 / 15, b. 40 / 9, c. 15 / 8, d. 9 / 4, e. 15 / 4
b

Problem: the sum of first n consecutive odd integers is n ^ 2. what is the sum of all odd integers between 15 and 41 inclusive.
Options: a. 351, b. 392, c. 410, d. 424, e. 450

b