A train leaves Station A heading East at 60 mph. At the same time, another train leaves Station B heading West at 40 mph on the same track. The stations are 200 miles apart. How far apart will the two trains be exactly one hour before they collide?
100 miles
The relative speed between the two trains closing in on each other is 60 + 40 = 100 mph. Therefore, one hour prior to collision, they must be 100 miles apart.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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