Kode #195: hints & solution
Here's the clue board for Kode #195. Start with the spoiler-free hints. If you're still stuck, the full step-by-step solution is below, hidden until you open it.
Play Kode #195The 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.
- 15417▲1●1
- 22619▲0●2
- 31874▲1●1
- 42071▲0●3
- 52546▲0●0
Spoiler-free hints
- Exactly one of the four digits is 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 5 (2 5 4 6) has no marks at all, so 2, 5, 4, and 6 are not in the code.
- Row 1 (5 4 1 7) has 2 marks still unexplained, and only 2 digits are left undecided: 1 and 7. So both are in the code.
- Row 2 (2 6 1 9) has one mark still unexplained, and only one digit is left undecided: 9. So it is in the code.
- Row 3 (1 8 7 4) has 2 marks, already accounted for by 1 and 7. That rules out 8.
- Row 4 (2 0 7 1) has one mark still unexplained, and only one digit is left undecided: 0. So it is in the code.
- That makes all four digits of the code: 0, 1, 7, and 9. Every other digit is out, which also rules out 3.
- Row 1 (5 4 1 7) has one digit in the right spot. Since row 2 rules out the 1 in position 3, it has to be the 7 in position 4.
- Row 3 (1 8 7 4) has one digit in the right spot. Since the 7 is already in position 4, it has to be the 1 in position 1.
- The 0 has only one spot left: position 3 (row 4 rules out position 2, position 1 is already 1, and position 4 is already 7).
- That leaves the 9 for position 2.
That cracks it: the code is 1907.