## Unsolvable Logic Problem!

A forum for good logic/math puzzles.

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JSchiffel
Posts: 1
Joined: Fri Feb 25, 2011 3:48 pm UTC

### Unsolvable Logic Problem!

Hello:
I have bought this book full of puzzles and questions like this one, but I can't solve this question. I just can't figure out the pattern. I'm new in all this stuff and don't know how to upload images, so I will do it with smilies, haha:
mmm mmm
mmm mmm
mmm mmm

mmm mmm
mmm mmm
mmm mmm

mmm mmm
mmm mmmms
mmm mmm

So, as u can see, you have to find the 9th square, which is a . In that square, where should be placed? Consider the phone format for giving your answers, that is:
1 2 3
4 5 6
7 8 9
So, if u think should be in the middle of the 9th square, write 5. I would like to see an explanation, though. Thanks!

AaronJMiller
Posts: 9
Joined: Mon Feb 21, 2011 10:20 am UTC

### Re: Unsolvable Logic Problem!

Maybe I'm missing something, but... 9? 9 is the only one left and I'm not sure that order is actually important here.

Cheers,
Aaron.

Spambot5546
Posts: 1466
Joined: Thu Apr 29, 2010 7:34 pm UTC

### Re: Unsolvable Logic Problem!

3, 4, and 6 are also unrepresented.
"It is bitter – bitter", he answered,
"But I like it
Because it is bitter,
And because it is my heart."

redrogue
Posts: 116
Joined: Tue Dec 15, 2009 9:17 pm UTC

### Re: Unsolvable Logic Problem!

Spoiler:
I believe it's 2.

Assume the grins travel in a loop that goes 1->4->7->8->5->2->1. Treat each row individually.

The first row travels from 8 one step to 5. Then two steps to 1... so 1 step then two steps.
The second row travels from 1 two steps to 7. Then 3 steps to 2... so 2 steps then three steps.

We sort of have a pattern that goes n steps, then n+1 steps.

The third row travels from 7 one step to 8. So assuming it follows the pattern, it should travel two steps to position 2.

coversation
Posts: 2
Joined: Sat Feb 26, 2011 4:41 am UTC

### Re: Unsolvable Logic Problem!

Spoiler:
I believe that the answer is 3 because in the first row, the numbers are 2, 5, and 7. Add the first two together and you get the third: 2 + 5 = 7. In the second row, the numbers are 7, 1, and 8. Again, add the first two and you get the third: 7 + 1 = 8. So the third row numbers are 1, 2, and X. 1 + 2 = X therefore X = 3.

EDIT: I realized that the main post said to use a phone-type layout after I posted my solution which uses a keyboard num pad-type layout.

HonoreDB
Posts: 160
Joined: Tue Feb 06, 2007 4:32 pm UTC
Contact:

### Re: Unsolvable Logic Problem!

Does the book itself hint that you should think of it as a phone grid, or was that just your suggestion for communicating the answer? I suspect it's the latter, which means it's a sort of puzzle I'm not very good at. If we ARE supposed to be thinking of it as a number grid, then

Spoiler:
Treat it as separate modulo 10 subtraction problems down the columns. 8-1=7. 5-7=8. 1-2=9. The missing square would be 9.

Scyrus
Posts: 124
Joined: Tue May 11, 2010 8:32 pm UTC
Location: Portugal

### Re: Unsolvable Logic Problem!

Spoiler:
:(

charonme
Posts: 141
Joined: Sun May 18, 2008 11:18 am UTC

### Re: Unsolvable Logic Problem!

the problem with these is that they are so short that almost any answer can be justified with multiple different explanations. So the real puzzle is not to find the "correct" one, but "the one the puzzle creator was thinking about".

ScottVR4
Posts: 2
Joined: Mon Aug 04, 2008 8:05 pm UTC

### Re: Unsolvable Logic Problem!

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Last edited by ScottVR4 on Sun Dec 31, 2017 6:16 pm UTC, edited 1 time in total.

Ddanndt
Posts: 60
Joined: Fri Oct 02, 2009 4:18 pm UTC
Location: Paris

### Re: Unsolvable Logic Problem!

Well at first I thought it was braille cos they weren't using the 3rd column but no good. Also I also seem to see a swastika pattern but yeah this puzzle is one of the hardest I've seen (even having finished puzzle books) ...
God does not care about our mathematical difficulties — He integrates empirically.
—Albert Einstein

Randomizer
Posts: 284
Joined: Fri Feb 25, 2011 8:23 am UTC
Location: My walls are full of hungry wolves.
Contact:

### Re: Unsolvable Logic Problem!

So, are we trying to complete the sequence or the grid? It's a bit ambiguous. I mean like...

The tic tac toe grid:
O|X|O
X|O|X
O|X|?

Is different than the sequence OXOXOXOX?

In the first one the answer would be X because in tic tac toe X gets an extra turn and in the second it would be O because OXOXOXOXO is a palindrome.
Belial wrote:I'm all outraged out. Call me when the violent rebellion starts.

Jonathanvt
Posts: 6
Joined: Wed Apr 22, 2009 6:54 am UTC

### Re: Unsolvable Logic Problem!

A pretty wild guess of mine and its reasoning:
Spoiler:
3. That's the only way rows and columns have the same (permuted) distribution, 4-4-1.

Edit: snazzy diagram time:

Code: Select all

_ _ _   _ _ _   # _ _---1
_ _ _   _ # _   _ _ _---|-1
_ # _   _ _ _   _ _ _---|-|-1
| | |
# _ _   _ _ _   _ # _---2 | |
_ _ _   _ _ _   _ _ _---|-0 |
_ _ _   # _ _   _ _ _---|-|-1
| | |
_ _ _   _ _ _   _ _ #---1 | |
_ _ _   _ _ _   _ _ _---|-0 |
# _ _   _ # _   _ _ _---|-|-2
| | |   | | |   | | |   4 | |
2-|-|---1-|-|---1-|-|-4   1 |
1-|-----2-|-----1-|---4   4
0-------0-------1-----1