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.
--------
Question: Problem: cathy and jim begin running at the same time and they start at the same place on a straight path. cathy runs at 10 miles per hour, and jim runs at 6 miles per hour. after 18 minutes, cathy stops to stretch. if it takes cathy 27 minutes to stretch and jim continues to run during this time, how many minutes will it take cathy to catch up to jim ?
Options: a. 20.5, b. 21.5, c. 22.5, d. 23.5, e. 24.5

Answer: c

Question: Problem: if price of t. v set is reduced by 20 %, then its sale increases by 80 %, find net effect on sale value
Options: a. 44, b. 45, c. 46, d. 47, e. 48

Answer: a

Question: Problem: 100 people are attending a newspaper conference. 45 of them are writers and more than 36 are editors. of the people at the conference, x are both writers and editors and 2 x are neither. what is the largest possible number of people who are both writers and editors ?
Options: a. 26, b. 24, c. 18, d. 20, e. 22

Answer:
c