Kode #172: hints & solution
Here's the clue board for Kode #172. 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.
- 10259▲1●1
- 24213▲0●2
- 36148▲0●2
- 43891▲0●0
- 56594▲1●2
Spoiler-free hints
- 3 of the four digits are even.
- The four digits add up to 17.
- 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.
- Row 4 (3 8 9 1) has no marks at all, so 3, 8, 9, and 1 are not in the code.
- Row 2 (4 2 1 3) has 2 marks still unexplained, and only 2 digits are left undecided: 4 and 2. So both are in the code.
- Row 3 (6 1 4 8) has one mark still unexplained, and only one digit is left undecided: 6. So it is in the code.
- Row 5 (6 5 9 4) has one mark still unexplained, and only one digit is left undecided: 5. So it is in the code.
- Row 1 (0 2 5 9) has 2 marks, already accounted for by 2 and 5. That rules out 0.
- That makes all four digits of the code: 2, 4, 5, and 6. Every other digit is out, which also rules out 7.
- Row 1 (0 2 5 9) has one digit in the right spot. Since row 2 rules out the 2 in position 2, it has to be the 5 in position 3.
- Row 5 (6 5 9 4) has one digit in the right spot. Since row 3 rules out the 6 in position 1 and the 5 is already in position 3, it has to be the 4 in position 4.
- The 2 has only one spot left: position 1 (row 2 rules out position 2, position 3 is already 5, and position 4 is already 4).
- That leaves the 6 for position 2.
That cracks it: the code is 2654.