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7/9/2013 3:04:21 PM

Purple Pisces
Purple Pisces
Posts: 878
As much as I love Cross Sums I'm no expert so other solvers may have a different opinion from mine. When I hit a tough area of a puzzle I'll mentally fill in a number and see if it will work. I wouldn't call it trial and error though because I'm not physically filling in the number and following through several steps to see if it will work. Usually with this scenario of mentally plugging in a number I'm able to rule out either a large or small digit which helps me find the right one from remaining possibilities.

I think I would have a much easier time solving Cross Sums if I penciled in the possibilities for each square when I reach a tough spot, much like in Sudoku, but I like using my Frixion pens too much when doing these puzzles! smile

So I would say logic is involved instead of trial and error, though the logic may always not be so easy to see.

7/9/2013 4:08:53 PM

Frances
Frances
Posts: 698
I try to use logic only. When really stumped, I do pencil in a couple of possiblities and keep solving on them to see which won't work out. Is that trial and error? While I'm sure logic alone can solve a Cross Sums, like Purple said, that logic might be missed. But to me the logic of these puzzles is no where near the complexity of some sudokus! After years of solving Cross Sums, I think just familiarity with certain sums has proved to be the most helpful! smile

7/9/2013 6:24:06 PM

Frances
Frances
Posts: 698
I never found the "cheat sheet" to be very helpful. It just seems quicker for me to scribble in the puzzle margins or on blank paper. This also allows me to mark off those possibilities that won't work as the solve progresses. And, on sums of 6 to 8 digits it is easier for me to simply mark on the outside of the diagram near the sum what isn't there, instead of checking the list to figure which numbers are missing from or included in a sum. For example, the numbers 1 to 9 added together = 45. So:

8 digits=44 has no 1; =43 has no 2; =42 has no 3; etc.
7 digits=42 has no 1 or 2; =41 has no 1 or 3; =28 has no 9 or 8; =29 has no 9 or 7.
6 digits=39 has no 1,2,3; =38 has no 1,2,4; =21 has no 9,8,7; =22 has no 9,8,6.

The first thing I do on a puzzle is to mark any of the above on the outside of the diagram. That helps.

7/9/2013 7:17:42 PM

Purple Pisces
Purple Pisces
Posts: 878
I don't use a cheat sheet but like Frances will make notes in the margins. I don't know how the puzzle is set in the variety magazines, but in the Dell's Logic and Math they leave quite a nice size space next to the puzzle to allow for notes. I am familiar with the more common group of sums such as 9,8 & 7=24, 9,8 & 6=23, 1,2 & 3=6, 1,2 & 4=7, and such and hope that the more I do Cross Sums, the easier the more advanced ones will come to me.

One thing I do when solving is count the cells for a sum and try to figure out which numbers I won't be using. For example say there is a sum of 35 with 7 cells. I know that that I won't be using two digits that will equal 10. Because no number can be used twice I know a 5 must be used. And if there are any digits already filled in it will help me figure out what other digits are used also. For example if a 6, 7, and 9 are filled in, I know that a 4, 3 and 1 will also be used. This leaves the digits 2 and 8 to be unused for that cell. This is the method I use a lot when trying to figure out these puzzles.

7/10/2013 6:05:13 PM

Frances
Frances
Posts: 698
Bernadette1959 wrote:
PS. I went to check to make sure I had listed the title of the Solver's Choice Easy Fast'n Fun magazine correctly and realized that it is no longer listed in the product menu. I guess they've done away with it for some reason. The PennyPress version is still there but not the Dell.


About 4 years ago "Easy Fast 'n' Fun Variety" was renamed "Solvers Choice Easy Fast 'n' Fun Variety". They were still selling an issue for this summer (Volume #80), and had the subscription for the magazine still listed as available in the July Dell Official Variety Puzzles. The Product Map listing says "....not currently available. Please check back at a later date." That suggests some change, maybe frequency of issues. (Penny used to have another easy variety called "All-Star", in addition to "Good Time" and "Easy & Fun".) I can't see Dell not having any easy variety. But I guess we'll have to wait and see, though! smile

7/14/2013 1:19:49 PM

Purple Pisces
Purple Pisces
Posts: 878
After reading your post Bernadette I went and looked at the logic magazines as well! The selection seems smaller than I remember. In addition to the British Logic, I don't see Dell's Logic and Sudoku. I can't remember if there was another title, but I know there used to be more than 3. I'm bummed about the British logic problems, those were a favorite of mine as well, and Amy's too if I'm remembering correctly.

Maybe Penny/Dell can tell us what's going on.

7/14/2013 4:22:39 PM

Frances
Frances
Posts: 698
Oh, gee. I sure hope the British Edition Logic isn't being discontinued. It is one of my favorites. I'm going to hold on to "not currently available" and "check back at a later date" to mean temporarily unavailable for subscription. Otherwise, a big phooey. upset

P.S. I've mentioned this before, but I wish we had a spot on this site just to ask questions of the editors.

7/14/2013 4:49:03 PM

Amy Lowenstein
Amy Lowenstein
Posts: 1599
Everybody is right that I like the British logic magazines. I have a few old ones from a super-sale a year or 2 ago where you got 28 assorted logic magazines for one low price. There were something like 6 British ones in that group, and I think I've worked 2 or 3 of those British ones so far. Maybe I'll switch to another variety for a while and save the last few British ones for later.

--
Amy

7/15/2013 3:51:33 PM

Purple Pisces
Purple Pisces
Posts: 878
I asked them on Facebook about the two logic titles, asking them if they are being discontinued. Will post the reply I get here.

7/16/2013 12:16:57 PM

admin
admin
Administrator
Posts: 108
Yes, unfortunately, both Original Logic Problems British Edition and Logic Lover's Sudoku & Logic Problems magazines will no longer be published. OLP British Edition's last issue will be Autumn 2013 and LLS&LP's last issue will be Winter 2013. We know many of you love logic magazines, and while it will be hard to say goodbye (we'll miss them, too), we can suggest a few alternatives. Logic Lover's Math and Logic Problems may be a suitable alternative to LLS&LP and you might try Original Logic Problems, which has some of the humor you've enjoyed in the British Edition.

Keep puzzling,
Admin



Purple Pisces wrote:
After reading your post Bernadette I went and looked at the logic magazines as well! The selection seems smaller than I remember. In addition to the British Logic, I don't see Dell's Logic and Sudoku. I can't remember if there was another title, but I know there used to be more than 3. I'm bummed about the British logic problems, those were a favorite of mine as well, and Amy's too if I'm remembering correctly.

Maybe Penny/Dell can tell us what's going on.

7/16/2013 1:28:29 PM

Purple Pisces
Purple Pisces
Posts: 878
Administrator,

Thank you for posting your answer here as well as on Facebook. I do have a subscription to Dell's Math & Logic Problems, but always enjoyed the British Edition Logic Problems as well. In my opinion the British Logic has a different look and feel from the other logic titles that will be greatly missed!

7/16/2013 2:35:32 PM

Frances
Frances
Posts: 698
Well, dang it. And in my opinion, Original Logic Problems isn't a suitable alternative to the British Edition. The humor, wit, vocabulary, cute little squiggly drawings, and just plain Englishness of the latter was unique. I just bought 3 back issues of British Edition from 2009 on Ebay. That'll help a little. smile

7/18/2013 2:13:15 PM

Indiana Puzzler
Indiana Puzzler
Posts: 559
Is it possible to purchase some back issues of the British Edition only?

admin wrote:
Yes, unfortunately, both Original Logic Problems British Edition and Logic Lover's Sudoku & Logic Problems magazines will no longer be published. OLP British Edition's last issue will be Autumn 2013 and LLS&LP's last issue will be Winter 2013. We know many of you love logic magazines, and while it will be hard to say goodbye (we'll miss them, too), we can suggest a few alternatives. Logic Lover's Math and Logic Problems may be a suitable alternative to LLS&LP and you might try Original Logic Problems, which has some of the humor you've enjoyed in the British Edition.

Keep puzzling,
Admin



Purple Pisces wrote:
After reading your post Bernadette I went and looked at the logic magazines as well! The selection seems smaller than I remember. In addition to the British Logic, I don't see Dell's Logic and Sudoku. I can't remember if there was another title, but I know there used to be more than 3. I'm bummed about the British logic problems, those were a favorite of mine as well, and Amy's too if I'm remembering correctly.

Maybe Penny/Dell can tell us what's going on.

7/18/2013 3:03:18 PM

Purple Pisces
Purple Pisces
Posts: 878
I called Customer Service the other day to see if I could and was told no.

8/29/2013 3:52:28 PM

Purple Pisces
Purple Pisces
Posts: 878
Looking back over the last couple posts, it's interesting how things change in just over a month. I wonder if they got the idea to do British Logic value packs from reading this thread!

8/29/2013 5:39:45 PM

Amy Lowenstein
Amy Lowenstein
Posts: 1599
Hey, congratulations, Purple. I just realized you're over 500. Woo hoo! And you may indeed be right that the editors, when seeing how popular the British logic puzzles are with us forum-goers, decided to make some value-packs of British puzzles.
edited by Amy-in-PA on 8/29/2013

--
Amy

8/29/2013 9:09:32 PM

Purple Pisces
Purple Pisces
Posts: 878
Thanks Amy! smile

3/7/2016 4:39:27 PM

Josh
Josh
Posts: 170
Circling back to the original topic of Cross Sums, I've found as I solve them more regularly again I can begin to see the sort of patterns they lay out so you can logically narrow it down to one number. On the hardest ones I still pencil in now and then, but the vast majority I can now solve just by analyzing it for a bit. I now challenge myself to see how far I can go without writing in the combinations. Same with Sudoku, really.

3/31/2016 8:29:00 PM

JohnJSal
JohnJSal
Posts: 135
Cross Sums are one of the puzzle types that I still haven't gotten around to solving yet. They seem pretty difficult, and seem to require a knowledge of the tons of possible number combinations.

One of these days I'll do one, just like I finally got around to learning all the others that used to seem so intimidating.

3/31/2016 11:25:43 PM

Josh
Josh
Posts: 170
JohnJSal wrote:
Cross Sums are one of the puzzle types that I still haven't gotten around to solving yet. They seem pretty difficult, and seem to require a knowledge of the tons of possible number combinations.

One of these days I'll do one, just like I finally got around to learning all the others that used to seem so intimidating.



Understanding the combinations definitely helps. I can see the unique ways forward much more quickly because I've gotten to the point where I can find the combinations even on the longer strings much faster now. Definitely one of the puzzles where practice strengthens ability.

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