There are 12 coins. Out of which one is odd one i.e weight is less or more. How many iterations of weighing are required to find odd coin and determine its weight relative to the others

Sure, here is the solution:

1. Divide the 12 coins into three groups of 4 coins each.

2. Weigh two of the groups against each other. There are two possible outcomes:

   a. The scales balance. This means that the odd coin is in the group that was not weighed. Move to step 3.

   b. The scales do not balance. This means that the odd coin is in one of the groups on the scales. Move to step 4.

3. If the odd coin is in the group that was not weighed, divide this group into 4 individual coins. Weigh two against two.

   a. If the scales balance, the odd coin is the one that was not weighed. This is the 2nd iteration.

   b. If the scales do not balance, the odd coin is one of the two on the scale. Weigh these two coins against each other to find the odd one out. This is the 3rd iteration.

4. If the odd coin is in one of the groups on the scales, divide this group into 4 individual coins. Weigh two against two.

   a. If the scales balance, the odd coin is the one that was not weighed. This is the 2nd iteration.

   b. If the scales do not balance, the odd coin is one of the two on the scale. Weigh these two coins against each other to find the odd one out. This is the 3rd iteration.

So, it will take a maximum of 3 iterations of weighing to find the odd coin and determine its weight relative to the others.