A cylindrical tank is half full of water. If you pour out 15 liters, the tank becomes one-third full. What is the total capacity of the tank in liters?
90 liters
Let C be capacity. Half full = 0.5C. One-third full = (1/3)C. 0.5C - 15 = (1/3)C. (1/2 - 1/3)C = 15. (1/6)C = 15. C = 90 liters.
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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