Step 1: As per hint 4, remove ‘7’, ‘3’ and ‘8’ from other hints
Step 2: From hint 5, we can say ‘0′ should be present whose position might be 1st or 2nd but not 3rd.
Step 3: Hint 1 and hint 2 specify that ‘6’ can not be the number as it says 1 number is correct but wrong placed/well placed.
Step 4: Hint 3 shows ‘2’ and ‘0’ will be the number, and
hint 1 shows ‘2’ will be in last place of code.
Step 5: With
hint 3 and
hint 5, we can say ‘0’ will not be on 2nd and 3rd position. So, it will be in 1st position of code.
Step 6: Only 2nd place left, and
hint 2 says one number is correct but wrong placed. ‘6’ is already removed. ‘1’ is also removed because correct number will not be in second place. Number is ‘4’ now left in that set of numbers, and hence it is the correct but misplaced one.
So therefore, the actual combination to open the lock is 042!