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.

Input: Consider Input: Problem: for the past n days, the average ( arithmetic mean ) daily production at a company was 50 units. if today ' s production of 110 units raises the average to 55 units per day, what is the value of n ?
Options: a. 9, b. 11, c. 13, d. 15, e. 17

Output: b


Input: Consider Input: Problem: a theater box office sold an average ( arithmetic mean ) of 63 tickets per staff member to a particular movie. among the daytime staff, the average number sold per member was 78, and among the evening staff, the average number sold was 60. if there are no other employees, what was the ratio of the number of daytime staff members to the number of evening staff members ?
Options: a. 2: 3, b. 1: 4, c. 1: 5, d. 6: 11, e. 4: 7

Output: c


Input: Consider Input: Problem: the ratio between the length and the breadth of a rectangular park is 3: 2. if a man cycling along the boundary of the park at the speed of 12 km / hr completes one round in 7 minutes, then the area of the park ( in sq. m ) is
Options: a. 153200, b. 153400, c. 153600, d. 154000, e. 117600


Output: e