instruction:
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: 50 % of a number is more than 40 % of 120 by 180. find the number ?
Options: a. 456, b. 480, c. 420, d. 445, e. 320
answer:
a

question:
Problem: for each color copy, print shop x charges $ 1.20 and print shop y charges $ 1.70. how much greater is the charge for 40 color copies at print shop y than at print shop x ?
Options: a. $ 14, b. $ 16, c. $ 18, d. $ 20, e. $ 22
answer:
d

question:
Problem: if 8 men or 12 women can do a piece of work in 30 days, in how many days can the same work be done by 6 men and 11 women ?
Options: a. 10 days, b. 11 days, c. 13 days, d. 15 days, e. 18 days
answer:
e