Kode #75: hints & solution
Here's the clue board for Kode #75. 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.
- 16403▲1●1
- 26892▲0●2
- 32654▲0●1
- 49457▲1●1
- 58205▲0●0
Spoiler-free hints
- Exactly one of the four digits is even.
- The four digits add up to 25.
- 3 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.
- Row 5 (8 2 0 5) has no marks at all, so 8, 2, 0, and 5 are not in the code.
- Row 2 (6 8 9 2) has 2 marks still unexplained, and only 2 digits are left undecided: 6 and 9. So both are in the code.
- Row 3 (2 6 5 4) has one mark, already accounted for by 6. That rules out 4.
- Row 1 (6 4 0 3) has one mark still unexplained, and only one digit is left undecided: 3. So it is in the code.
- Row 4 (9 4 5 7) has one mark still unexplained, and only one digit is left undecided: 7. So it is in the code.
- That makes all four digits of the code: 3, 6, 7, and 9. Every other digit is out, which also rules out 1.
- Row 1 (6 4 0 3) has one digit in the right spot. Since row 2 rules out the 6 in position 1, it has to be the 3 in position 4.
- Row 4 (9 4 5 7) has one digit in the right spot. Since position 4 is already 3, it has to be the 9 in position 1.
- The 6 has only one spot left: position 3 (row 3 rules out position 2, position 1 is already 9, and position 4 is already 3).
- That leaves the 7 for position 2.
That cracks it: the code is 9763.