Words Of Wisdom on 18 September 2008
| nordlead said: ok, a new problem for those who read this thread You have a pile of 24 coins. Twenty-three of these coins have the same weight, and one is heavier. Your task is to determine which coin is heavier and do so in the minimum number of weighings. You are given a beam balance (scale), which will compare the weight of any two sets of coins out of the total set of 24 coins. How many weighings are required to identify the heavier coin? |
12 on each side for the first weighing. 12 are eliminated.
6 on each side for the second weighing. 6 are eliminated.
3 on each side for the third weighing. 3 are eliminated.
1 on each side for the fourth weighing.
If one is heavier, that's the one. If they are the same, the one you didn't weigh is the heavy one.
