The Faulty Coin Puzzle

You have 8 identical-looking coins, but one of them is slightly heavier. You have a balance scale and can only use it twice. How can you find the heavier coin?

Answer:

  1. Divide the coins into three groups: two groups of 3 and one group of 2.
  2. Weigh the two groups of 3 coins.
    • If one side is heavier, the heavier coin is in that group.
    • If they balance, the heavier coin is in the group of 2.
  3. Weigh two coins from the heavier group (whether it’s 3 or 2 coins) to find the heaviest one.
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