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 train of length 250 m crosses a bridge of length 150 m in 20 seconds. what is the speed of train ?
Options: a. 33, b. 27, c. 25, d. 22, e. 72

SOLUTION: e

PROBLEM: Problem: the arithmetic mean and standard deviation of a certain normal distribution are 14.5 and 1.7, respectively. what value is exactly 2 standard deviations less than the mean ?
Options: a. 10.5, b. 11, c. 11.1, d. 12, e. 12.5

SOLUTION: c

PROBLEM: Problem: the l. c. m of two numbers is 495 and their h. c. f is 5. if the sum of the numbers is 100, then their difference is
Options: a. 19, b. 10, c. 28, d. 27, e. 29

SOLUTION:
b