let's have a look at this puzzle do feel free to kind of copy the puzzle down and have a go at yourself first and let's see how we get on you know pause it and have a think about it if you like and we'll see how we do so I'm seeing some ones down the middle here a1 in column 4 and column 5 the one in column 6 has to be in this box can't be here because of that one so it can go in there that's nice start might put in some pencil marks as usual the only place in eight can be in this box is in one of those two cells because of this 8 and this 8 nines over here can only be in those two places in that box 5 5 here and a 5 here and a 5 here places us a 5 in the very central square that gets a survived on here you can see that that 5 and that 5 will allow all those 5 squares and that fibrils out that one so 5 is either here or here 8 now because of this 8 cutting out those 2 squares and this 8 8 is either here what else have we got ones down here so that puts us one either here yeah and 5 here 5 by the hero yeah there at 5 you can see cuts out those 3 squares and that five can't see out those three that just leaves those two in the last box.
now I might be missing something doesn't seem to be much else to go on so where do we go next eights here actually there's an eighth in row seven and row eight so the eights in this box must be in one of those two positions and look now this is interesting this five this five in column two is cutting out those two cells this five in row eight is cutting out those two and that now gives us a 5/8 pair so because fives and eights have to be in one of those two boxes we know that's appear in some order and that is interesting because now all the corner squares are not available in this box for numbers other than two four six five they look at this nine where can the nine go can't go here or here can't go in these two squares because of the 5/8 pair so it must be in one of these two squares and we have a one nine pair the last two cells in this box are reserved seven and three because that's all that's left so although we've only got one or two seven threes given in the grid we know that those are seven and three in some order that's kind of a hidden pair and that think that might prove very useful seven six three nine five eight in the column hmm okay.
seven in the top left box must be on the left-hand side and they've got that seven as well how about one nine nine in this box must be in one of the corners because we've got a nine there and one of these is a nine it's very important with these pairs to remember how powerful their being and look those fives have removed the possibility of five said this squares of five ah and look six in column eight and a six in row eight and that's ruled out five of the empty squares in that box there goes six six is either there or there in box and must be in column seven in that box one looks seven is not in row five there and not in column nine so seven must be either there or there in that box and one oh this is good look one can't be here or here because of this one and it can't be here or here because of this one so one is either here or here and we've we kind of know to within one box where three four five eight one seven six and nine go that leaves just two for this so in fact I think that was obvious yeah I mean they were all they were all prevented from being anything other than a – well done if you spotted that earlier that's good work and that too restricts – in the central box – either they're there and – over here is either there or now just feels like this is ready to crack open somehow seven eight three two five six one must be at the right hand side at the top.
now I mean well done if you're picking up the next stage ahead of me and that's quite possible we're not superhuman what should I be looking for here like five still think we didn't quite make enough of that seven seven three pair that was so surprisingly available that must be one two or Ford that must be two or four I can't quite see how to decide yet that's either four or nine but don't know which it's nearly giving up its secrets this puzzle but not quite two must be either here or yeah then that doesn't advance us very much yes so it is this cell isn't it here and just as I was saying earlier it's worth remembering the pairs we've got one nine in that pair of cells there and with one nine six stopping not available for this cell and seven eight three to five above it it's only possibility remaining is a four so now we can put a one nine pair in this box as well up here that turns this eight pair into into an eight four pair and that gives us two three as the only remaining possibilities there that resolves this to here there it is five four six eight two one three also can't be there as well that same two three pair that we've put in at the top so three is one of those this is now seven or nine and look there is a nine in that pair so it's the seven and that means that this isn't three nine pair and that's quite nice now that resolves this group of cells that were one six nine and seven they must be in this order and that's a one box completely filled there now we must have a one look we've got a 1 in row 5 and a 1 in row 6.
the one in Row 4 has to be in this box it's a 1 and so we've got a 1 in column 1 and column 3 in this box and a 1 in column 1 and column 3 in this box so the one in the top box must be in column 2 and we've got a 1 there to decide where it is so in goes our next one that resolves this one 9 pair and we're making good progress now we've just got two and four to fill in in that column where are we going now so yes this is the reigning cell in this row so that's the three five one two six nine mm-hmm decide between four and seven they are but that three puts three over here in column 6 and that means the 3 in column 5 must be up at the top now look in over here 3 was restricted to rows 2 & 3 here 3 is restricted to rows 2 & 3 so here 3 must be at the top don't know which one yet but again it's further elimination 3 1 7 3 2 R this cell there's only one possibility remember 3 2 8 5 1 in the column five nine four seven in the row this has to be a six and that fixes the six down here which we needed to figure out which one it was 6s 5.37 is one of these two not sure which yet five six net force surely that six helps bit more yes it does the six in this box at the top can't be in column 4 or 5 so it must be over here in column 6 and that's made another so that's an eight-six pair given this 9 and the fact that it can't be in one of those two cells it must be at the top as well and that puts a nine in one of these two sails making them another pair five and nine pair so we have five nine eight one two must be either there or there.
now seven three six six can't be in the top two because of this one and it can't be in the central one because of this one now the five nine pairs blocking those two six must be down the bottom of that box and that resolves this six eight there that resolves this eight four pair does that take us forward finally 9:45 still that's 2 or 4 that's 2 or 4 we don't quite know which is which 5 double sixes failing an incredibly close to a complete finish here well done if you're ahead of me again you may well be at this point one of those is a 4 but 7 is still possible in several cells ah 6 in the middle row 6 there six there six there that place is our six here that resolves six in the top left box that resolves to now we know that's a four this is a two we're just eliminating these as we go 5 4 9 6 7 1 & 2 are up in the top of this box 8 & 3 are at the bottom but we don't know the Audient but that resolves the threes or they were resolved in any way they're 7 and 4 in summer water and I think we are pretty much on the homestretch now into once six where should we go to finish off our two three pair that's been resolved there that three isn't that useful yeah I mean the only possibility left in this row
row two we've got a five nine pair in the left box so we need a for now and that resolves this four which fixes nine we get the four seven there they're sorted this is a three no it's not it's a nine now and what else do we have in this box three and seven there has to be three this is seven that fixes the seven there this is for three now the top and that resolves the three eight pair that resolves the eight five pair we've got the nine one pair sorted and now this is the nine summary the nine five pair resolved there seven goes down here it's the last number for the books and the column seven three there and that disambiguate this three nine pair loads and loads of pairs in that New York part New York Times puzzled quite a nice puzzle and I mean you had lots of opportunities to go faster than me there I hope you did but all we really needed to do was find these kind of hidden pairs the eight five pair was was almost given at the start the nine one pair came fairly quickly and that gave us the seven three pair and then we had to find a few cells where there was only one possibility and I struggled for a while finding that four over there but once that was done it was fairly straightforward so hope that was at least somewhat instructive for you and thank you.