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: 54671 - 14456 - 31466 = ?
Options: a. 2449, b. 5449, c. 8749, d. 8449, e. 6468

Answer: c


Question: Problem: two trains travel in opposite directions at 36 kmph and 45 kmph and a man sitting in slower train passes the faster train in 8 seconds. the length of the faster train is
Options: a. 80 m, b. 100 m, c. 120 m, d. 180 m, e. 160 m

Answer: b


Question: Problem: a train covers a distance in 50 min, if it runs at a speed of 48 kmph on an average. the speed at which the train must run to reduce the time of journey to 40 min will be.
Options: a. 60 kmph, b. 63 kmph, c. 57 kmph, d. 70 kmph, e. 61 kmph

Answer:
a