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: what is the rate percent when the simple interest on rs. 810 amount to rs. 155 in 4 years ?
Options: a. 4.78, b. 4.68, c. 4.58, d. 4.48, e. 4.38

SOLUTION: a

PROBLEM: Problem: a fort had provision of food for 150 men for 45 days. after 10 days, 25 men left the fort. find out the number of days for which the remaining food will last.
Options: a. 44, b. 42, c. 40, d. 38, e. 36

SOLUTION: b

PROBLEM: Problem: a cube is divided into 216 identical cubelets. each cut is made parallel to some surface of the cube. but before doing that, the cube is painted with green on one set of opposite faces, red on another set of opposite faces, and blue on the third set of opposite faces. how many cubelets are painted with exactly one colour ?
Options: ['a. 72', 'b. 84', 'c. 96', 'd. 108', 'e. 120']

SOLUTION:
c