Cognik

A pause between pages

A little puzzle. A new idea.

Choose your answer, then reveal the reasoning. This is the same question as the Cognik App Clip.

Which option has exactly one different character from the reference?

XWHN

  1. AX2HN
  2. BXWHN
  3. CWXHN
  4. DXHWN
Reveal the answer

Answer A

Apply the requested comparison rule to the reference and keep only the single candidate that matches that rule exactly.

  1. Read the target rule

    Look for the candidate with one and only one changed position.

  2. Lock the reference

    Memorize XWHN as a 4-character reference before checking the options.

  3. Compare each candidate in sequence

    Option A, X2HN: Position 2: expected “W”, shown “2” Option B, XWHN: All positions match. Option C, WXHN: Position 1: expected “X”, shown “W”; Position 2: expected “W”, shown “X” Option D, XHWN: Position 2: expected “W”, shown “H”; Position 3: expected “H”, shown “W”

  4. Reject the near-miss options

    Discard exact copies and discard options with two or more changed positions, because only one single substitution is valid.

X2HN is correct because it is the only candidate with exactly one changed character. Position 2: expected “W”, shown “2”

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