Two trains are heading toward each other on the same track, both traveling at 50 mph, exactly 200 miles apart. A very fast bird starts flying from the front of the first train toward the second train at 75 mph. When it hits the second train, it immediately turns around and flies back to the first train, repeating this until the trains crash. How total distance does the bird fly?
150 miles
The trains are 50 mph each, so their closing speed is 100 mph. At 200 miles apart, they will crash in exactly 2 hours (200 / 100 = 2). Since the bird flies at 75 mph continuously for those 2 hours, it travels 75 * 2 = 150 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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