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 distance between the stations is 100 miles. A bird flies back and forth between the fronts of the two trains at 80 mph until the trains collide. What total distance does the bird fly?
80 miles
The trains close the 100-mile gap at a combined speed of 60 + 40 = 100 mph, meaning they collide in exactly 1 hour. The bird flies at a continuous 80 mph for that 1 hour, covering 80 miles.
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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