



 
Hi Chris. Let's use T to represent the number of hours between the time train B leaves the station and the time it catches up to train A. Then train B goes 50 x T miles, right? When you multiply the speed by the time, you get the distance. Now remember that train A had a 12 minute head start. That's 0.2 hours. So train A has travelled at 40 mph for T + 0.2 hours. So its distance traveled from the station is 40 x (T + 0.2). But haven't both trains gone the same distance? You should be able to form an equation and find the value of T. Hope this helps,  


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