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Coin weighing: three answers per weighing.
Play Coin Weighing
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How to play Coin Weighing
- Put the same number of coins on each pan.
- Press Weigh.
- When only one suspect is left, press That's the fake and tap it.
Tips and strategy
- Split the suspects into three groups, not two.
- Coins you leave off the scale are a group too.
- In the 12-coin puzzle, weigh 4 against 4 first.
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FAQ
Coin Weighing: questions
How do you find the fake coin in 9 coins with 2 weighings?
Weigh 3 against 3. If they balance, the fake is in the other 3; if not, it is in the heavier group. Then weigh 1 against 1 from that group.
How is the 12-coin puzzle solved?
Weigh 4 against 4, then use the result to choose a clever second weighing that mixes coins between pans. The game lets you try it.
Why does the scale seem to know my plan?
It always gives the answer that leaves the most coins suspicious, so only a plan that works in every case can win.
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