Task: Question Answering
Input (English): Problem: two trains, a and b, started simultaneously from opposite ends of a 125 - mile route and traveled toward each other on parallel tracks. train a, traveling at a constant rate, completed the 125 - mile trip in 12 hours; train b, traveling at a constant rate, completed the 125 - mile trip in 8 hours. how many miles had train a traveled when it met train b ?
Options: a. 25, b. 37.5, c. 40, d. 45.5, e. 50
Output (English): e