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? Choose the correct option.
A) 25  B) 37.5  C) 40  D) 45.5  E) 50
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= 
<gadget id="calculator">  125*8/20</gadget>
<output>50</output>
50 miles.   Answer: 50.
<result>E</result>
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?