A cylindrical glass is filled with water exactly to its halfway point. When the glass is tilted until the water level forms a diagonal line that touches the very top rim and the opposite bottom edge, what percentage of the original water remains inside the glass?
50%
When a uniform cylinder is tilted so the water surface touches the top rim and the opposite bottom edge, the water forms a right-angled triangle of empty space at the top and a matching triangle of water at the bottom. Because the water forms this precise geometric cross-section across the cylinder's axis, the volume of water remains exactly half of the total cylinder capacity.
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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