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?
Answers
A) 25 B) 37.5 C) 40 D) 45.5 E) 50

Rationale: as the ratio of the rates of a and b is 8 to 12 then the distance covered at the time of the meeting ( so after traveling the same time interval ) would also be in that ratio , which means that a would cover 8 / ( 8 + 12 ) = 8 / 20 of 125 miles : 125 * 8 / 20 = 50 miles . answer : e .
Answer: E