The Clever Version Of LinkedIn's Mini Sudoku!!

Added: 2026-05-25

[00:00:11][music] >> Hello and welcome to Saturday's edition of Cracking the Cryptic where we're going to be doing something just slightly different today, I think. Um I would guess that 95% of the puzzles that we are sent or that are recommended to us are what most people would describe as pretty difficult puzzles. Um you know, they take Mark and I sometimes well over an hour, sometimes well over two hours. It has been known to take four hours to solve a puzzle.

[00:00:44]Um and and that's fine and that's the the general trend of of puzzle difficulty, I think, has has increased over the years. There's sort of been difficulty inflation. Um but we are always on the look lookout for puzzles that are slightly easier, but crucially retain that level of interest and beauty that means that they, you know, that they're going to be enjoyed by an audience. And this puzzle called 10x + y by Cactus Love is one such example. This is a one-star uh out of five difficulty rated puzzle on Logic Masters, but um if I show you the comments, they're just wonderful.

[00:01:24]And I mean, it's still got a huge a huge approval rating on Logic Central Mouse.

[00:01:29]See, still doesn't work. Um but look, everybody's just saying it's a great puzzle, nice little puzzle, fun, delight. Um I Thank you very much for creating and sharing this little math puzzle. Glad you added in base 10. What's that about?

[00:01:45]I don't [laughter] know.

[00:01:46]Is it Oh yes, okay, that is in the instructions. Um Anyway, Cactus Love is is one of my favorite constructors. Um he's actually been on a little bit of hiatus recently.

[00:01:58]Come back Cat as love.

[00:02:00]And well, this is what we're going to have a go at today.

[00:02:04]I saw I saw in one of those comments on Logic Masters that somebody had done this puzzle in under 5 minutes. So, if you fancy yourself as a bit of a speed demon, that's that's a challenge for you. Anyway, we'll read the rules which are very short for this one in a moment or two's time. What can I tell you about before that?

[00:02:20]Over on Patreon, we've got the solution videos for this month's monthly reward.

[00:02:24]Uh this which was Spider-Man obviously, the Spider-Man hunt.

[00:02:28]If you did get stuck on any of those and we did get one or two comments that a couple of the puzzles had sticky points in them.

[00:02:35]You can watch the videos over on Patreon now and see how to get yourselves unstuck. Very very well done to the hundreds and hundreds of you that managed to finish the entire thing and we will draw the winner shortly.

[00:02:49]I rely on Mark for that. He he knows how to generate random numbers from the computer.

[00:02:55]Um So, anyway, we'll we'll do the winner winner in a in a day or two's time.

[00:03:01]Other than that, what else to mention?

[00:03:03]We should be back in the Blueprints Mansion on Monday night. So, we'd love to have your company for that if you're free. I see if we can find that watering can.

[00:03:13]And I've got a couple of birthdays to do. Let's have a look the birthday list.

[00:03:17]Oh, what's that say?

[00:03:19]Uh no, that's fine. That's a WhatsApp message about wine of all things.

[00:03:24]Um Andrea.

[00:03:27]Andrea, it's your birthday today. I know this because your boyfriend Santiago wrote to me.

[00:03:33]Apparently, the two of you watch the channel together of an evening. So, thank you both for watching. I'm going to try and say, is it Feliz cumpleanos?

[00:03:43]I thought that's going to be utterly butchered.

[00:03:47]I I Uh Santiago asked if I could try and say that in Spanish. I I did my best um and um yeah, I hope I hope I hope it was at least intelligible slightly um Andrea and I hope well, I hope obviously today is a day full of gifts and an enormous chocolate cake with lots of chocolate icing.

[00:04:07]And then oh am I late with this one?

[00:04:11]Yes, I'm a day late with this one. I'm so sorry Steve.

[00:04:14]Um your wife Nicole wrote to me and um and asked if we could say uh wish you a happy birthday um and um I know that you watch a lot of the shorts content. I think you started with Madel Madel. That's that's what I I should I should certainly refer to him as Madel from now on. Uh I think you watched Mark's Wordle videos uh >> [laughter] >> originally.

[00:04:39]And then you've got more and more into cryptic crossword content. So, you've started to find our minute cryptic videos, etc. Um so, thank you for watching. I hope you even get this message. You might might not watch enough long messages to get it, but Steve, many happy returns. I hope the chocolate cake yesterday was up to scratch.

[00:04:56]Now, let's have a look at Cactus Laughs puzzle. Uh 10x + y. What do we have to do with this one? We've got normal 6 by 6 Sudoku rules applying. So, we're going to have to put the digits 1 to 6 once each in every row, every column and every 2 by 3 rectangle.

[00:05:14]Um digits along an arrow sum to the two-digit number shown in the attached pill, read left to right in base 10. I suppose you could make a version of this that would be quite a lot more difficult if we weren't using base 10.

[00:05:27]Um but what that means is if this was sort of 16, that well, that's how you would read that. 16 and then the arrow would have to and that's going to be wrong, isn't it? But that arrow would have to add 16 is how the rules work.

[00:05:43]Do you have a go. The way to play is to click the link under the video as usual.

[00:05:47]But, now I get to play. Let's get cracking.

[00:05:53]I mean, let's let's deal firstly with I think the misinformation almost provided in the title of this puzzle, 10x + y. I mean, that is sort of useful.

[00:06:06]But, so I think what Cactus Luv is leading us towards there is is is if we put the numbers 1 and 6 in here.

[00:06:15]Obviously, from a mathematical perspective, the sum of this arrow is 16. It's not 1 6. So, how do we turn the numbers 1 and 6 into the number 16? We times the tens digit by 10, 10x, and we add the units digit on.

[00:06:35]So, [snorts] if we wanted to know what the sum um of the whole row was, well, there's a few things we could think about, isn't there? Um how could we express all of those digits mathematically?

[00:06:54]Well, as Cactus Luv tells us, let's put x and y in. If this is x and this is y, we know that the arrow adds up to 10x + y.

[00:07:06]But, the whole row includes another x and another y, if you see what I mean. So, this is 10x + y, this portion of it. Ooh, terrible choice of color. So, the indigo portion adds to 10x + y.

[00:07:20]And once we add the digit x and the digit y to 10x + y, we get 11x + 2y.

[00:07:28]So, the whole row is equal to 11 times this digit plus two times this digit. Now, we can do stuff with this, I think, to do with parity.

[00:07:40]Because the secret in a 6 by 6 Sudoku, which is not the same as the secret of Sudoku for a 9 by 9 Sudoku, but it's it's going to be important, isn't it?

[00:07:51]Because and it's something I share with only my very, very favorite people. If you're watching this video about 6 by 6 Sudoku, my goodness, you're in that small part of the Venn diagram that makes you absolutely one of my favorite people.

[00:08:06]So, we we know what the sum or we know that any row, any column, and any rectangle of a 6 by 6 Sudoku contains the digits 1 to 6 once each. If we add 1 to 6 up, we get the triangle number for 6. 1 + 2 + 3 + 4 + 5 + 6 is 21. So, I know that the sum of this row is odd.

[00:08:25]So, remember the equation, 11x + 2y.

[00:08:32]If this was an odd number, if it Oh, sorry. Let's do it the other way around. If this is an even number, 11 * an even number will be an even number plus another even number, because the whole row adds to 2 * y, so 2y is even as well. And that would imply that 21 was even. Well, that can't be right.

[00:08:52]So, this is going to have to be a 1.

[00:08:54]And that's a very complicated way of I've I've sort of demonstrated that, but that that sort of how one could go about thinking about this um sort of in a in a holistic way. And once we've got one here, we know that the 11x part of our equation for the whole row adds to 11.

[00:09:17]So, 11x + 2y is equal to 21.

[00:09:22]So, this 2y is equal to 10. So, y is equal to 5. And then we can sort of check whether this is going to make sense. So, 15 for here + 5 + 1, that is 21, isn't it? So, I mean, we could do that, uh if we wanted to.

[00:09:40]But but at least maths works. That's what we've discovered there.

[00:09:44]Um Now, okay, when we were doing the example, I was looking at this pill, and I was I put 16 into this and realized it was immediately wrong. I suspect this has to be a two.

[00:09:58]Because if we think about this portion of the line, what's the sum of those digits? Well, again, that's got to be the digits one to six once each. So, that's 21's worth of digits.

[00:10:09]Now, whatever this digit is, we're never going to get this tens digit up to be a 30-something number. We can't put nine in here.

[00:10:18]It's a one to six Sudoku. So, this is definitely a two.

[00:10:24]Um And the the same principle applies here, doesn't it? In the sense that we know the entirety of this line does add up to 11 times this digit plus two times this digit.

[00:10:39]And it Oh, okay. Okay. Okay. So, we could even We could even do this by elimination, couldn't we?

[00:10:46]In the sense that So, we know that this is 21.

[00:10:55]So, if this was, I don't know, a six, this would be 27. That's not going to work.

[00:11:02]Um if this is four, this would need to be 25. It's not going to work. The difference between those has to be has to be one, and this has to be the higher digit. So, 24, you can We can already see it's going to work. 24, this is now a six.

[00:11:18]I I mean, I I can totally see how you could do this puzzle very quickly, but I'm sort of enjoying just exploring the principles involved in it a little bit.

[00:11:27]Now, this is a very That's not one or two.

[00:11:32]Okay, let's think about that in the context of the bottom two boxes all together.

[00:11:37]Because we do know the sum of the entirety of those two boxes, don't That's going to be two lots of 21, which is 42.

[00:11:46]So.

[00:11:50]So.

[00:11:52]Oh, goodness. Sorry, there's a storm blowing through and I didn't I didn't um close my door, so it's decided to slam.

[00:12:00]Um Right. So, we can see that this tens digit is either a three or a four. Now, let's imagine for a moment it was a four.

[00:12:09]We know that this digit is not zero.

[00:12:12]Oh, dear, it really is getting blowy. It might slam again in a moment. I'm sorry if that that this does make a noise.

[00:12:18]Um Don't do it. Naughty door. Um Yeah, so as we know that everything there would sum to 42.

[00:12:29]So, if this is the minimum it could be, that would be a 41, wouldn't it? 41 would be left for the remaining remainder of all of those digits minus those two digits to get to the sum of the line. So, there's no way that this can be a four digit because it would imply that um well, it just would be nonsense. 1 + 4 + whatever this is would be deducted from 42 to get the total of the line.

[00:12:55]So, this is going to be a three.

[00:12:57]Again, let's use the principle. We now know that this this digit, if you like, accounts for 33 of the overall sum of this uh of this entire line.

[00:13:12]So, we've got 33 plus something, which is going to be 2 Y, isn't it? So, if this was let's say it was a five, that's already too big because then we would have 43 for the line.

[00:13:28]But we know that the whole box sums to 42. If this was a one, let's try the an alternative. If this was a one, I shouldn't have tried five anyway. I've not been doing any Sudoku in this puzzle really. If this was 31, then we'll be on 33 plus two is 35.

[00:13:51]And this would have to be uh a seven to get us to 42. So, that definitely doesn't work either.

[00:13:59]But if this is two, it might work, mightn't it?

[00:14:02]33 plus four is 37, and then this could be a five, and that would work.

[00:14:09]I think that's going to have to be how it works. So, it's going to be a five here, a two here. Now, if this is a six, did I check that one? No, it's going to be too big cuz we've already we've already looked at five. Five was too big. 36 would take us up to 33 plus 12 uh for the for those digits, which is too much again, 45 not even including this number. So, this is 32.

[00:14:34]This is five.

[00:14:38]Um well, this this tens digit has to be a one because we can't make this arrow add up to 20-something even if we put four and six in there.

[00:14:49]4 + 5 + 6 is 15, isn't it? So, this is going to be a one.

[00:14:53]So, again, remember we're we're adding the whole all of those digits add up to 11x, so 11 plus this digit here.

[00:15:03]Um Now, how should we do this?

[00:15:09]Oh, is there is there a is there a jolly beautiful way to do it?

[00:15:14]There could well be with a cactus love puzzle.

[00:15:17]Oh, in fact, also Yeah, well, we can do we can actually do a little bit of Sudoku here, can't we?

[00:15:24]Because this tends to check for a three-digit line will have to be a one.

[00:15:28]We can't add it up to 50 or 60. So, we get all of those digits entered.

[00:15:34]And and a one in the corner and a one here and a one here. Just doing a little bit of Sudoku.

[00:15:41]Um we're allowed to repeat digits on lines, aren't we? So, this line could be double five plus six here. But, we do know that these Yeah, in fact, these digits add up to 11.

[00:15:53]So, they must be a five-six pair and the order's known from Sudoku.

[00:15:58]Now, these digits are two, three, and four.

[00:16:01]Um and how should we do this? Well, you can already see I don't know it's obvious, but that's going to be a two, isn't it?

[00:16:11]Because five plus three plus four is equal to 12. Um and if we go for anything else here, then what let's try 13 and just see why it breaks.

[00:16:21]Um that would imply using our 11x + 2y situation that would be on 17 here.

[00:16:29]Well, we can't make those add up to 17.

[00:16:31]It's just too big.

[00:16:33]Um so, that's going to be a two. This is a three-four pair. That's a two by Sudoku.

[00:16:40]This is a four by Sudoku. It can't be a three.

[00:16:44]And Okay, and these are three, five. So, we can put the three in.

[00:16:51]Put the five and the six in. Write a two in the corner.

[00:16:56]And are we sort of done now?

[00:16:59]I mean, that there's obviously Sudoku to do and we can do that. But, the the sort of mathematics of the puzzle I think has have been have Yeah, they've gone away, haven't they? So, now we're sort of in LinkedIn mini Sudoku mode to finish it off. So, it it was it is quite a simple puzzle, by modern cracking the cryptic standards. I think I think 6 years ago on the channel this would have been a normal difficulty puzzle. And actually I think for some people this would be plenty difficult enough because the concept of tens digits and units digits having to be multiplied by 10 would be as mathematical a thing as they probably seen it in in life. If you haven't done much maths um in your life or you haven't or you neglected maths in school, it really would be it you know that even even this I think would be challenging.

[00:17:54]But hopefully um well hopefully you agree that was rather pretty. And also hopefully you might encourage you do share it. Do try and get more people into this wonderful hobby that we all share.

[00:18:08]Um I think this is the sort of thing that might be a nice gateway.

[00:18:13]Uh and let let's see some of your fastest times in the comments. Um and I I'll if somebody No, honest times as well. You can't just say 1 second. I'm not going to believe that. What do I Okay, let me think about that. What would the fastest solver in the world solve this puzzle in?

[00:18:33]I'm going to get I I'm going to say I don't know if Channer Tarann will be watching this, but if I think Chan would do this in a just over a minute. Might be wrong.

[00:18:46]That that would be my guess.

[00:18:48]Anyway, let me know how you got on in the comments. I enjoyed I enjoyed the comments especially when they're kind.

[00:18:53]And we'll be back later with another edition of Cracking the Cryptic.