One of the eighty-five coins is relatively light, and it will take at least a few times to find it.

You have to weigh it at least four times to find this coin. The method is as follows:

1: Choose one at random, then divide the 84 coins into three parts, each with 28 coins, and weigh the two parts to find out the lighter one. light

Coins are in it.

2. Choose another coin, divide the 27 coins into three parts, weigh the two parts, and find out the lighter one.

Coins are in it.

3: Divide the nine coins directly into three parts, three parts for each part, or two parts, and find the lighter one.

4: Take any two of the three coins, and if they are balanced, the remaining coins are light coins; If it is unbalanced, the upturned end is a light coin.

Original, hope to adopt. . . . . .