Kode #126: hints & solution
Here's the clue board for Kode #126. 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.
- 19527▲1●1
- 24621▲0●2
- 37510▲0●1
- 45028▲0●0
- 51862▲1●0
Spoiler-free hints
- 2 of the four digits are even.
- The four digits add up to 26.
- 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 4 (5 0 2 8) has no marks at all, so 5, 0, 2, and 8 are not in the code.
- Row 1 (9 5 2 7) has 2 marks still unexplained, and only 2 digits are left undecided: 9 and 7. So both are in the code.
- Row 3 (7 5 1 0) has one mark, already accounted for by 7. That rules out 1.
- Row 2 (4 6 2 1) has 2 marks still unexplained, and only 2 digits are left undecided: 4 and 6. So both are in the code.
- That makes all four digits of the code: 4, 6, 7, and 9. Every other digit is out, which also rules out 3.
- Row 5 (1 8 6 2) has one digit in the right spot, and the 6 in position 3 is its only digit in the code, so it's locked in.
- Position 1 can only be 9 (row 2 rules out 4 and row 3 rules out 7).
- Row 1 (9 5 2 7) has only one digit in the right spot, already accounted for by the 9 in position 1. So the 7 isn't in position 4.
- The 7 has only one spot left: position 2 (row 1 rules out position 4, position 1 is already 9, and position 3 is already 6).
- That leaves the 4 for position 4.
That cracks it: the code is 9764.