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.

Ex Input:
Problem: in a mayoral election, candidate x received 1 / 2 more votes than candidate y, and candidate y received 2 / 5 fewer votes than z. if z received 25000 votes how many votes did candidate x received ?
Options: a. 18000, b. 22500, c. 24000, d. 26000, e. 32000

Ex Output:
b


Ex Input:
Problem: john and david can finish a job together in 2 hours. if john can do the job by himself in 3 hours, what percent of the job does david do ?
Options: a. 36.33 %, b. 33.33 %, c. 39.33 %, d. 40.33 %, e. 33 %

Ex Output:
b


Ex Input:
Problem: the average of 45 results is 25 and the average of other 25 results is 45. what is the average of all the results ?
Options: a. 24, b. 32, c. 48, d. 50, e. none

Ex Output:

b