Help with USA Today puzzle from 5/22

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Help with USA Today puzzle from 5/22

Postby lightningbug » Wed May 28, 2008 6:31 pm

I'm so glad to have found this forum that doesn't speak "fish-ese" so I've just joined. I would appreciate a push in the right direction on this.

I can usually do sudokus. I can certainly do USA Today four star ones. But this one has me truly stuck, and although I've asked other friends, they're stumped too. Heres the original puzzle:

Code: Select all
. . . | . 4 8 | 9 . 2
. . . | . 6 . | . 5 .
. . . | 1 . . | 7 6 .
------+-------+------
. 1 . | 2 8 . | . . 3
. . 3 | . 1 . | 8 . .
2 . . | . 7 4 | . 1 .
------+-------+------
. 3 8 | . . 2 | . . .
. 9 . | . 3 . | . . .
6 . 1 | 8 5 . | . . .



Here's how far I've got:

Code: Select all
1      567  567    |  57   4  8    |  9     3   2
34789  47   2      |  79   6  39   |  14    5   148
34589  45   459    |  1    2  359  |  7     6   48
-------------------+---------------+----------------
4579   1    45679  |  2    8  569  |  456   49  3
459    456  3      |  569  1  569  |  8     2   7
2      8    569    |  3    7  4    |  56    1   569
-------------------+---------------+----------------
45     3    8      |  46   9  2    |  1456  7   1456
457    9    457    |  46   3  1    |  2     8   456
6      2    1      |  8    5  7    |  3     49  49


I know for sure my big numbers are correct. I just need a breakthrough of some sort to carry on, but I can't see a thing. What am I missing?

Thanks for your time!
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Postby ArkieTech » Wed May 28, 2008 8:28 pm

Lightningbug,

Do you see the two cells with candidates 4 and 9 in row 9 columns 8 and 9? These two cells will have to wind up being either a 4 or a 9 so all other 4's and 9's can be removed from the lower right box.

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Re: Help with USA Today puzzle from 5/22

Postby daj95376 » Wed May 28, 2008 8:33 pm

lightningbug wrote:I know for sure my big numbers are correct. I just need a breakthrough of some sort to carry on, but I can't see a thing. What am I missing?

Thanks for your time!

Well, you missed 2x Naked Pair, a Locked Candidate 1, and a Locked Candidate 2. You should have found those. That still leaves a Naked Quad to finish up before a bunch of Singles.
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I'm a clot

Postby lightningbug » Thu May 29, 2008 4:11 am

Thanks for the advice. Unfortunately, idiot that I am, I pressed spacebar before copying the puzzle, and got all the possiblities, not my own notations. THIS is actually how far I am:

Code: Select all
1      567  56     |  57   4  8    |  9     3   2
3489   47   2      |  79   6  39   |  14    5   148
34589  45   459    |  1    2  359  |  7     6   48
-------------------+---------------+----------------
579    1    5679   |  2    8  569  |  456   49  3
459    456  3      |  59   1  569  |  8     2   7
2      8    569    |  3    7  4    |  56    1   569
-------------------+---------------+----------------
45     3    8      |  46   9  2    |  156   7  156
457    9    457    |  46   3  1    |  2     8   56
6      2    1      |  8    5  7    |  3     49  49


So thanks for the help daj, but I did get that. I'm still stuck past that.

And thank you for the help Arkie, but although I have been doing sudokus for over a year now, I don't know a naked, amorous pair from a modestly clothed platonic one because I don't understand the jargon!

Sorry for the extra trouble.
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Re: Help with USA Today puzzle from 5/22

Postby Cec » Thu May 29, 2008 5:08 am

lightningbug wrote:".... been doing sudokus for over a year now, I don't know a naked, amorous pair from a modestly clothed platonic one because I don't understand the jargon..."

Hi lightningbug,
I think you'll find the following link will explain these things for you.
http://www.angusj.com/sudoku/hints.php

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Re: Help with USA Today puzzle from 5/22

Postby udosuk » Thu May 29, 2008 7:52 am

daj95376 wrote:That still leaves a Naked Quad to finish up before a bunch of Singles.

lightningbug wrote:So thanks for the help daj, but I did get that. I'm still stuck past that.

Hi lightningbug, I think you didn't get the last bit from daj95376. In the top left 3x3 box, look for 4 cells containing the digits {4567}. So all other cells in that box can't have {4567}. This is what we call a Naked Quad.

Alternatively, there are only 2 cells in the leftmost column/top left 3x3 box which possibly have the digits {38}. So they must hold these 2 digits and nothing else. This is what we call a Hidden Pair.

:idea:
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Thank you!

Postby lightningbug » Fri May 30, 2008 10:05 am

Thanks Udosuk! I should have spotted that pair. I've never had to spot a quad before. My skills improve thanks to all of you.

And thanks, Cec for the link. That page does look understandable. I will have to study it sometime.

Thanks so much all! I think I can go on from there.
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