Kode #6: hints & solution
Here's the clue board for Kode #6. 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.
- 17190▲1●1
- 27492▲0●1
- 37135▲0●2
- 41763▲1●0
- 52679▲0●0
Spoiler-free hints
- 2 of the four digits are even.
- The four digits add up to 10.
- Just one digit is 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 (2 6 7 9) has no marks at all, so 2, 6, 7, and 9 are not in the code.
- Row 1 (7 1 9 0) has 2 marks still unexplained, and only 2 digits are left undecided: 1 and 0. So both are in the code.
- Row 2 (7 4 9 2) has one mark still unexplained, and only one digit is left undecided: 4. So it is in the code.
- Row 4 (1 7 6 3) has one mark, already accounted for by 1. That rules out 3.
- Row 3 (7 1 3 5) has one mark still unexplained, and only one digit is left undecided: 5. So it is in the code.
- That makes all four digits of the code: 0, 1, 4, and 5. Every other digit is out, which also rules out 8.
- Row 1 (7 1 9 0) has one digit in the right spot. Since row 3 rules out the 1 in position 2, it has to be the 0 in position 4.
- Row 4 (1 7 6 3) has one digit in the right spot, and the 1 in position 1 is its only digit in the code, so it's locked in.
- The 4 has only one spot left: position 3 (row 2 rules out position 2, position 1 is already 1, and position 4 is already 0).
- That leaves the 5 for position 2.
That cracks it: the code is 1540.