Challenge yourself to crack the code and open the 3 digit number lock using least number of clues. Time to solve the number lock puzzle is 10 mins.
Crack the Code Puzzle to Open a Number lock with 548 in Clues
From the five clues, find the three-digit code that will open the number lock.
- Clue 1: Code 548: One digit is right and is in its place.
- Clue 2: Code 806: One digit is right and is in the wrong place.
- Clue 3: Code 530: All digits are wrong.
- Clue 4: Code 157: Two digits are right, but both are in the wrong place.
- Clue 5: Code 647: One digit right and is in the wrong place.
Crack the code using least number of clues.
Solution to Crack the Code Puzzle to Open a Number lock with 548 in Clues
Identify two correct digits at one go
From Clues 3 and 4, digits 1 and 7 are both correct.
- Clue 3: Code 530: All digits are wrong.
- Clue 4: Code 157: Two digits are right, but both are in the wrong place.
With digit 5 wrong in Clue 3, the digits 1 and 7 must be correct in Clue 4.
Identify the third correct digit
From Clues 1 and 5, Digit 4 is wrong:
- Clue 1: Code 548: One digit is right and is in its place.
- Clue 5: Code 647: One digit right and is in the wrong place.
Digit 4 cannot be right and occupy the same position in both clues. This is identification of incorrect digit by conflict in two clues.
From Clues 1 and 3, digit 8 is right and occupies 3rd position in correct code.
- Clue 1: Code 548: One digit is right and is in its place.
- Clue 3: Code 530: All digits are wrong.
With digits 4 and 5 both wrong, digit 8 must be the single correct digit in Clue 1.
Crack the code to open the number lock
From Clue 4 crack the code:
- Clue 4: Code 157: Two digits are right, but both are in the wrong place.
Digits 1 and 7 are correct but in wrong positions.
For digit 1 position 1 is wrong and position 3 already occupied by 8. So its position must be second and for digit 7 position is first.
Solution: Code to open the number lock is 718.
Verify the code against each of the clues.
The Clue 2 is not used at all. This is the fastest and most efficient solution.
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