Task: There are 3 versions of the counterfeit coin problem, each with increasing degree if difficulty. You are to solve each problem using any heuristics. Most importantily, list the thinking skills you have used to solve the problems.
Version one:
OO OO OO OO
You are given 8 coins. Of the 8 coins, one of them is a counterfeit coin which is lighter than the other coins. You are provided with a balance weighing scale. Using the balance weighing scale at most twice, explain the steps which you would take to identify the counterfeit coin.
Version 2:
OOO OOO OOO
Now, you are given 9 coins and 1 of them is a counterfeit coin. The counterfeit coin is heavier than the good coins. Explain how you would find the counterfeit coin using the balance weighing scale in only 2 weighings.
Version 3:
OOO OOO OOO OOO
Now, you are given 12 coins and 1 of them is a counterfeit coin. The counterfeit coin may be heavier or lighter than the good coin. Explain how you would find the counterfeit coin using the balance weighing scale in only 4 weighings.
