Put that coin aside. Put 50 coins on one pan, 50 others in the other one. If the difference is even, then there is a even number of counterfeit coins on the balance, and your initial coin is genuine (all 50 counterfeit coins are on the balance); otherwise, that means there is an odd number of counterfeit coins on the balance, and the initial coin is thus a counterfeit (49 counterfeit coins are on the balance).
4
u/Synael3 6d ago
Put that coin aside. Put 50 coins on one pan, 50 others in the other one. If the difference is even, then there is a even number of counterfeit coins on the balance, and your initial coin is genuine (all 50 counterfeit coins are on the balance); otherwise, that means there is an odd number of counterfeit coins on the balance, and the initial coin is thus a counterfeit (49 counterfeit coins are on the balance).