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Crack the Code to Solve Number Lock Puzzle with 548 in Clues

Crack the Code to Solve Number Lock Puzzle with 548 in Clues

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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