Kode #11: hints & solution

Here's the clue board for Kode #11. Start with the spoiler-free hints. If you're still stuck, the full step-by-step solution is below, hidden until you open it.

The clue board

Each row is a guess that's already been graded. ▲ means a right digit in the right spot; ● means a right digit in the wrong spot.

  • 10847▲1●1
  • 20527▲0●1
  • 35716▲0●2
  • 42834▲0●2
  • 58501▲0●0

Spoiler-free hints

  • 2 of the four digits are even.
  • The four digits add up to 20.
  • 2 of the digits are 5 or higher.

Try the hints first. The solution below walks through every deduction.

Step-by-step solution

Every Kode can be cracked by pure deduction, with no guessing. This board falls in 10 logical steps. Open the solution to follow them one at a time.

Show the solution · reveals the code

When a row "rules out" a position, it shows that digit there but its ▲ marks are already used up (or it has none), so the digit can't sit there.

  1. Row 5 (8 5 0 1) has no marks at all, so 8, 5, 0, and 1 are not in the code.
  2. Row 1 (0 8 4 7) has 2 marks still unexplained, and only 2 digits are left undecided: 4 and 7. So both are in the code.
  3. Row 2 (0 5 2 7) has one mark, already accounted for by 7. That rules out 2.
  4. Row 3 (5 7 1 6) has one mark still unexplained, and only one digit is left undecided: 6. So it is in the code.
  5. Row 4 (2 8 3 4) has one mark still unexplained, and only one digit is left undecided: 3. So it is in the code.
  6. That makes all four digits of the code: 3, 4, 6, and 7. Every other digit is out, which also rules out 9.
  7. Row 1 (0 8 4 7) has one digit in the right spot. Since row 2 rules out the 7 in position 4, it has to be the 4 in position 3.
  8. The 7 has only one spot left: position 1 (row 3 rules out position 2, row 2 rules out position 4, and position 3 is already 4).
  9. The 6 has only one spot left: position 2 (row 3 rules out position 4, position 1 is already 7, and position 3 is already 4).
  10. That leaves the 3 for position 4.

That cracks it: the code is 7643.