You are given 6 precious stones. Exactly 2 are counterfeit, they have the same mass, and each counterfeit stone weighs less than each real stone.
You may use a set of balance scales, but you can make only 3 weighings to isolate both counterfeit stones.
How can you do it?
Exactly 2 of these 6 stones are counterfeit. Both are lighter than the real stones. Use at most 3 weighings to isolate them.
A useful first question is whether the two fakes are in the same group of 3 or split across both sides.
Left pan
Drop stones here
Right pan
Drop stones here
Item tray
Drag stones from here onto either pan
Preview = case split; tap coins to move tray ↔ pans.
15 cases match history.
Pick 2 fakes from the full set of stones.
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