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: if a / b = 1 / 3, b / c = 2, c / d = 1 / 2, d / e = 3 and e / f = 1 / 10, then what is the value of abc / def ?
Options: a. 27 / 4, b. 27 / 8, c. 3 / 4, d. 3 / 20, e. 1 / 4
answer:
d


question:
Problem: if a train, travelling at a speed of 90 kmph, crosses a pole in 4 sec, then the length of train is ?
Options: a. 281, b. 125, c. 288, d. 100, e. 121
answer:
d


question:
Problem: a distributor sells a product through an on - line store, which take a commission of 20 % of the price set by the distributor. the distributor obtains the product from a producer at the price of $ 15 per item. what is the price that the buyer observers on - line if the distributor wants to maintain a 25 % profit on the cost of the item ?
Options: a. 18, b. 21.6, c. 22, d. 22.5, e. 24
answer:

e