TASK DEFINITION: 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: Problem: a man bought an article and sold it at a gain of 5 %. if he had bought it at 5 % less and sold it for re 5 less, he would have made a profit of 10 %. the c. p. of the article was
Options: a. 960, b. 980, c. 900, d. 970, e. 1000

SOLUTION: e

PROBLEM: Problem: the product x of two prime numbers is between 17 and 60. if one of the prime numbers is greater than 2 but less than 6 and the other is greater than 13 but less than 25, then x =
Options: a. 18, b. 29, c. 37, d. 44, e. 57

SOLUTION: e

PROBLEM: Problem: what is the unit digit of ( 6 ! * 3 ! / 3 ! * 4 ! ) ?
Options: a. 5, b. 6, c. 0, d. 3, e. 4

SOLUTION:
c