Your uncle has just given you part of his coin collection as a gift. There are twelve coins that he says are quite valuable, except that one of them is a fake.

They all look the same. Your uncle doesn’t know which one is the fake, but he does know that it is not the same weight as the real ones. Unfortunately, he doesn’t know whether the fake is too light or too heavy, just that it’s different.

All you have to help you figure out this puzzle is a balance.

How can you find the fake by weighing the coins? What is the minimum number of weighings you need to get a definite answer?

…try some Science Lab projects about…
Air & Space
Earth Science
Electricity & Magnetism
Properties of Liquids

…try some interactive experiments in our…
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…or test your skills at our…
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