Twelve balls, one odd
You have 12 identical-looking balls. Exactly one has a different weight - but you don't know whether it's heavier or lighter. With a balance scale and only 3 weighings, identify the odd ball and whether it is heavy or light.
Show hints (2)+
- Each weighing has three possible outcomes - how much information is that?
- Compare with the number of (ball, direction) possibilities.
Answer
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