Solve Number Lock Puzzle 940 in Minimum Steps

Can you crack open number lock puzzle 940 in just two powerful steps? Each clue shows the correctness of digits and their positions.

3 Digit Number Lock Puzzle With 940 in Hint Codes

Clue 1: Code 9 4 0: Two digits are correct — 1 in the right place and 1 in the wrong place.

Clue 2: Code 6 5 2: No digit is correct.

Clue 3: Code 6 2 5: No digit is correct.

Clue 4: Code 8 4 1: Two digits are correct but both are in the wrong places.

Clue 5: Code 6 1 4: Two digits are correct and in the right places.

Time to solve: 5 minutes.

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Solution to Number Lock Puzzle 940 in Minimum Steps

Step 1. First Breakthrough: Direct Digit Placement from Clues 2 and 5

Clues Used: 2 and 5.

• Clue 2: Code 6 5 2: No digit is correct.
• Clue 5: Code 6 1 4: Two digits are correct and in the right places.

Digit patterns behind the choice: Clue 2 eliminates 6, 5, and 2 entirely. Clue 5 then directly confirms two correct digits in their exact positions.

Logic analysis:

• From Clue 2: 6, 5, 2 are all wrong.

• From Clue (6 1 4): Since 6 is wrong, both 1 and 4 must be correct and in the right places => 1 in the middle, and 4 in the rightmost position.

• Partial Code: [ ? 1 4 ].

Step 2. Second Breakthrough: Positional Conflict and Final Digit Confirmation

Clue Used: 1.

• Clue 1: Code 9 4 0: Two digits are correct — 1 in the right place and 1 in the wrong place.

Reason for the choice: The clue shares already identified correct digit 4, and contains two new digit choices, one of which will be our third correct digit.

Logic analysis:

• From Clue 1 (9 4 0): 4 is correct but in the wrong place (rightmost in clue, but we've placed 4 in rightmost in the code) => Conflict! This means correct digit 4 cannot be the correctly placed digit in Clue 1.

• So, the correctly placed digit in Clue 1 must be the one of 9 or 0.

• 0 is eliminated by positional conflict, claiming already claimed rightmost position in the secret code by 4 => 4 is incorrect => 9 must be the second correct digit in (9 4 0) and is in its correct leftmost position.

Final Secret Code: [ 9 1 4 ].

Verification:

Let's verify the secret code 914 against all five clues:

• Clue 1: 9 4 0 => 9 correct and well-placed (left), 4 correct but wrongly placed (middle vs right) => Matches "two digits correct — 1 in right place, 1 in wrong place" => Correct.

• Clue 2: 6 5 2 => All digits wrong => Correct.

• Clue 3: 6 2 5 => All digits wrong => Correct.

• Clue 4: 8 4 1 => 4 and 1 correct but both wrongly placed => Correct.

• Clue 5: 6 1 4 => 1 and 4 correct and in right places => Correct.

All clues are satisfied by the code.

Key Strategies You Learned:

1. Direct Placement from "All Wrong" Clue: A clue that says "no digit is correct" (Clue 2 or Clue 3) instantly removes those digits from consideration, allowing immediate placement of correct digits from a following clue (Clue 5).

2. Positional Conflict for Elimination: When a digit's (1 rightmost) confirmed position in the partial secret code [ 9 ? 1 ] conflicts with the position of a correct digit in a clue [0 in (9 4 0)], it is confirmed as incorrect and helps identify the other correctly placed digit (9 in Clue 1).

3. Leveraging Overlapping Clues: Using multiple clues that share digits with the partial code quickly confirms the final digit and structure.

To enjoy solving many more such number lock puzzles, click here.

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