Puzzles
The jug puzzle that made a mathematician
You have an 8-litre jug full of water, plus empty 5-litre and 3-litre jugs. Using only pouring between the three — no measuring lines, no guessing — split the water into two equal 4-litre portions. How many pours does it take?
Reveal the answer
Seven pours: 8→5 (3,5,0), 5→3 (3,2,3), 3→8 (6,2,0), 5→3 (6,0,2), 8→5 (1,5,2), 5→3 (1,4,3), 3→8 (4,4,0). This class of puzzle was collected by W. W. Rouse Ball in his 1892 'Mathematical Recreations and Essays,' tracing back through Bachet de Méziriac and Tartaglia.
— W. W. Rouse Ball, Mathematical Recreations and Essays — Macmillan, 1892 (puzzle traced to Tartaglia and Bachet de Méziriac)
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