A heavy oil tanker vehicle needs to cross a wooden bridge rated to hold a maximum total weight of exactly 10,000 kilograms. The tanker itself weighs exactly 10,000 kilograms. Halfway across the bridge, a 200-gram bird lands on top of the tanker, yet the bridge does not collapse. Why?
The tanker burned off more than 200 grams of fuel while driving to the midpoint
By driving to the middle of the bridge, the tanker's engine consumed fuel, reducing the total vehicle weight by far more than the 200 grams added by the bird.
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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