Brain Teasers & Mental Math
The 8-ball weighing puzzle: you have 8 identical-looking balls; one is slightly heavier. Using a balance scale, find the heavy one in the minimum number of weighings.
Model answer
2 weighings.
Weighing 1: split into groups of 3, 3, and 2. Put 3 vs 3. • If they balance, the heavy ball is in the leftover 2 → weigh those 1 vs 1, the heavier side is it (weighing 2). • If one…
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