Train A leaves Station A heading east at 60 mph. Simultaneously, Train B leaves Station B heading west on the same track at 40 mph. The stations are 100 miles apart. A bird flies continuously back and forth between the fronts of the two trains at 80 mph until they collide. What total distance does the bird fly?
80 miles.
The trains close the 100-mile distance at a combined speed of 100 mph (60 + 40), meaning they will collide in 1 hour. Flying at 80 mph for 1 hour, the bird travels a total distance of 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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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