Fake Coin - Answer

Fake Coin:

I have 12 coins and out of which one of them is fake. The fake coin can only be distinguished by being either heavy or light. Can you determine which one is fake using only 3 weighings using a physical balance?

Answer:

Yes. You can identify the fake coin from 12 coins using 3 weighings.

First weighing:Take 8 coins and place four coins on each side of the physical balance. If it is equal, then we can move ahead to the remaining coins.

Second weighing:
Place 2 coins on each side of the physical balance. We can know which is side is heavier or lighter.
Third weighing:
From those 2 coins, place one coin on each side and we can find out the fake coin from the rest.

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