The Puzzle Can Be Solved Following a Series of Steps and Deductions, Explained Below
Spoiler: The correct answer to the “Can you open the lock using these clues?” riddle is 042. Now that you know the answer, you can read through the clues again and see how each one applies to the answer.
Because the fourth clue eliminates 7, 3 and 8 as possibilities, the fifth clue means that 0 is the correct number but in the wrong position. The third clue indicates that the right digits, including the 0, are in the wrong place. That means the 0 must be the first number of the code.
Based on the first and second clues, the 6 must be eliminated as a possibility because it’s in the same place in both clues, but one clue says it’s in the right place and the other clue says it’s in the wrong place. So by looking at the first clue, we can determine that 6 and 8 are both eliminated (the 8 due to the fourth clue), meaning that the 2 is right and in its place.
The final number can be solved using the second clue. Because the digit remaining to be solved is the second digit, the answer must be 4 and not 1. The digit is right but in the wrong place, so it can’t be 1, which is already in the middle, so it must be 4, meaning the full answer is 042.