Gribalko A.V.

On the Field of Wonders, 11 golden coins grew, but it became known that exactly four of them are counterfeit. All genuine coins weigh the same, and all counterfeit coins also weigh the same, but they are lighter than the genuine ones. Fox Alyosha and Buratino collected the coins and started dividing them. Alyosha is going to give Buratino four coins, but he wants to check first if they are all genuine. Can he do this with just two weighings on a balance scale without weights?
Let Pinocchio first put two of his coins on each of the pans. If one of the pans outweighs the other, then he has counterfeit coins among his.

In case of balance, Pinocchio may have 0, 2, or 4 counterfeit coins. Now he will put his coins on one pan and 4 of the Fox's coins on the other. If all of Pinocchio's coins are genuine, his pan will outweigh (since there are only 7 genuine coins in total), in the other cases - no, because in this case the Fox has no more than two counterfeit coins.

## Answer

## He will be able to.

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