Math homework has kid in tears and both parents stumped. How to solve it?

[@seannolan2120]

The problem they have is they look at the entire thing and panic. They dont have the patience to break the problem down and clearly the parents dont either

[@macchiato_1881]

US education system btw. "First world country"

[@Neckhawker]

Well, asking to use brute force is not a great thing either.

[@ghil263]

​@@macchiato_1881 what's your point? Why would you expect educational system to facilitate a creative, problem-solving mindset? Point is to entrain people to be order-following regurgitators who suspend judgment and outsource discernment to false authority

[@gdmathguy]

​@@NeckhawkerThe brute force is minimal, it's at most 3 cases

[@Neckhawker]

@@gdmathguy Still, this isn't fair to ask children to brute force when they are often asked to NOT use it.

[@happygamer787]

Not me pausing to solve the problem only to realise there's more rules😅

[@marvhollingworth663]

I did that too! 😆

[@SH3RIFFtheMobilePlayer]

Same here 😅

[@poldi2233]

Same. Then I unpaused because I couldn't solve it, saw the additional rules, paused again and solved it :D

[@dimavolkov8793]

Also didn't know the rules, just assumed that all blank spaces must be single digit, and solved it. When I saw all the rules it turned out much simpler 😅 no need for system of equations

[@timothyvenable3336]

100% haha

[@steves9250]

Unless the teacher is just giving these problems out at random, you also need to take into account what the students have been taught. Especially in regard to order of operations.

[@hikari1690]

It's not at random. Claude knows what he's doing 😂

[@JamesJones-ts5fl]

I would bet most of these aren’t real homework problems. Reddit and the media love to make random puzzles into “impossible to solve” or “little johnny was crying” headlines.

[@gbschweter]

Right now Mind Your Decisions has 3.14 millions subscribers!! Congratulations!!

[@Golfnut_2099]

Pi million subscribers. NICE!!!!!

[@Loadingandloaded]

PI

[@Skenjin]

I WISH i had gotten homework like that in school

[@DepDawg]

Me too! Would have been more interesting.

[@ShawnF6FHellcat]

My math grades were part of the reason that my school had to lower the maximum grade from 105 to 103... and that was when I was in Geometry... If this was homework and actually made kids cry, then I can quite confidently say that neither the kids, their teachers, nor their parents would like me for very much longer.

[@riluna3695]

I made the mistake of solving this off of just the thumbnail, and completely missed the restriction that you had to use 1 through 9 exactly once each. But I still got the same answer. I DID assume that I had to use 0-9 only, though; no negatives or double digits. But I ignored repeats. It just so happens that there weren't any :D It made the puzzle WAY harder, though. After the first three easy answers, I had to do a lot of comparing tiles to each other, and then testing to see if those combinations broke anything else. Whittle them down bit by bit, and the correct answer emerges all the same. It's neat that there's no ambiguity even if you allow for repeat digits. And it's neat that I accidentally invented, and completed, the Challenge Mode of this puzzle :P

[@Patterner]

Proper Gamer move😂

[@strifera]

Fun Fact: You don't need to know you can only use 1-9 exactly once. Simply knowing each space is a single digit is enough to solve the problem.

[@christophstahl8169]

you don't even need that. There is only one solution.

[@fewwiggle]

"Simply knowing each space is a single digit is enough to solve the problem." ​ @christophstahl8169 "you don't even need that. There is only one solution" How do you solve it when all numbers are available? (Once you fill in the obvious squares, there are six variables and only 5 equations)

[@Max_Griswald]

​@@christophstahl8169- Yeah, I screenshot the thumbnail, then used the screenshot editor to mark in the numbers and found there is only one solution.

[@compiling]

@@christophstahl8169 There are multiple solutions if you allow integers outside the range 1-9. e.g. you can fill in the remaining squares with 3,9,3,13,4,3. Since there's 5 equations and 6 unknowns, there will be an infinite number of solutions.

[@DoongXiouHua]

@@christophstahl8169 Nope. There are 2 solutions if numbers greater than 10 are allowed.

[@catbitmaster8216]

Actually, I think the fact that you have to use each number exactly once is a huge hint. Once the 1st and 3rd columns are solved (4 and 9, respectively), followed by 3rd row (3), things are pretty smooth from there by process of elimination. This is essentially sudoku meets formulas. 1. 1st row, can only be 1, 7; 2, 8; or 3, 9. Since 3 and 9 are taken, we know there are only 2 possible combinations. We put a pin on that. 2. 2nd row, can only be 1, 3; or 2, 8. Any number in the first spot would make the 2nd number requiring 2 digit. Since 3 is taken, it is clearly 2, 8. 3. Going back to 1st row, since 2 and 8 are taken, it is clearly 1, 7. 4. The last row is just 5, 6 (simply working out the formula using either number in place since there are only 2 possible workings).

[@MrMaelstrom07]

The stipulation each digit only once isn't necessary, but makes it easier for kids.

[@badhombre4942]

The 2nd row could be simplified to n x 5 = 2 + m. Then 2 + m must be a multiple of 5, giving m = 8 and n = 2.

[@Th3Curs3dChild]

That's a bit too advanced language for a problem meant for *~*-graders

[@legion162]

Good fun puzzle, not sure why people would struggle with it

[@DepDawg]

I think people look at it as one giant puzzle and feel overwhelmed, rather than solving one equation at a time.

[@rizkyadiyanto7922]

because its in the US.

[@Max_Griswald]

I think it just comes down to people not trying to find the correct/easiest place to start combined with the fact that the majority of people who graduate public school these days seem to have never heard of the order of operations.

[@MrShikaga]

Why “people” would struggle with it? You mean why 10 year olds would struggle? I dunno, because they are children, rather than adults who get math puzzles recommended to them by KZbin?

[@legion162]

@@MrShikaga the video title ".... and both parents stumped" I'm going to go out on a limb and say both parents were older than 10, I'd go as far as saying they were adults that should have been able to do basic math 🤷

[@verkuilb]

One thing which is interesting about this particular puzzle is that it follows “order of operations” rules. It is common for this type of puzzle to state that order of operations rules do NOT apply, and that calculations are to be assessed left-to-right (or top-to-bottom), the way a “traditional” calculator would assess them. From that perspective, this one is actually somewhat of an exception.

[@hikari1690]

Do they? That's interesting. It (the puzzles that don't take into account order of operations) shouldn't be used as a homework problem though cause it might give kids bad habits

[@phasm42]

I wonder if that's why the rightmost column had no blanks: to demonstrate order of operations.

[@YunxiaoChu]

@@phasm42perhaps

[@darreljones8645]

The first and last columns, in particular, are tough to understand if you don't know and use PEMDAS. The fractional division in the first column (4 / 8) could also be tricky for a fifth grader. It also doesn't help that a.) this grid is a 5-by-5, when most problems of this sort are in a 3-by-3 or 4-by-4 grid, and b.) two of the operations put the equals side closer to the middle (i.e., 3+4-5 = 9-7), while most other problems like this always put it just before the final number (i.e., 5-4+9-7 = 3).

[@marvhollingworth663]

Those puzzles have to tell you not to use pemdas because they know their method is actually wrong.

[@hbokaie]

Am I the only one who could not find how the 1st column works ?

[@undercoveragent9889]

9 - ((4/8) x 4) = 7

[@the12tones]

you are not the only one! thanks undercover, for explaining.

[@Mebsuta]

You have to use the order of operations.

[@MountainPieEnjoyer]

why? 9-4/8*4=7. Simplify using order of operations to 9-.5*4=7, followed by 9-2=7, and finally 7=7, which is true

[@marvhollingworth663]

I did it more like 1/2 x 4 = 2. Just a different way of looking at it & saying the same thing.

[@adventureboy444]

5:15 i did it a bit different because any number multiple to 5 will end with 5 or 0 at the end of the number there are 4 possibilities 0 + 6 = 6 10 - 4 = 6 (20 - 14 = 6) 5 + 1 = 6 15 - 9 = 6 (25 - 19 = 6) So we have to make so that 4 - x equal to 6, -4, 1, -9 (-14, -19 aren't possible with plus and minus on 1-digit number) Knowing that 1 is the smallest available on the list and 8 is the largest, we can eliminate some number Ranging from 4 - 1= 3 to 4 - 8 = -4, we can eliminate 6 and -9 4 - 3 = 1 and 4 - 8 = -4 so x (the fourth slot in the puzzle) can be 3 or 8 3 is already used so x = 8 By doing some simple algebra, we get 4 + 2 x 5 - 8 = 6 or 2 x 5 + 4 - 8 = 6

[@pigcatapult]

4:25 Oh, you did the second row fourth? I did the bottom one because I realized that x3-y=9, therefore x could only be 3, 4, 5, or 6. x couldn’t be 3 or 4, and x=6 would force y=9, which was also already used, therefore x can only be 5.

[@Torawakamaru]

I did this as well, which also leads to the fact that the blanks in columns 2 and 4 are both (x, x+1) (with x being the first row blank).

[@compiling]

Once you find that relation, you know that y is a multiple of 3 and since 3 and 9 have already been used it has to be 6.

[@worstwordmonger]

I found it easiest to solve the bottom row first when it got to 6 remaining digits. 7 = a x 3 - b - 2. Add 2 to both sides, and you get 9 = a x 3 - b. Since 9 is a multiple of three, and 3a is a multiple of 3, b must be a multiple of 3. 3 and 9 are already taken, so b must be 6. For the rest, after simplifying one column you know the lower missing digit is one more than the higher missing digit, and in simplifying the top row you know the left digit is six less than the right digit. It solves itself from there, since only 1,2,7,8 are left as consecutive pairs

[@marvhollingworth663]

I didn't bother with algebra, but I did the bottom row next too (after I was stumped for a bit & unpaused it to find the rule about each number once.)

[@ventsiR]

should define that equations should be read left ---> right / up ---> down, because I was reading the second right-most vertical equation down --> up

[@iandavies4853]

Exactly

[@erictrobin]

This kid in teas... is always the same one? Gosh

[@hikari1690]

It's the the Boston Tea Party all over again leaving kids in teas!

[@BigFellaDj]

🍵

[@erictrobin]

@@hikari1690 I knew this keyboad key wasn't woking

[@Neckhawker]

This kid is bullied by his teacher. Plot twits: the teacher is MindYourDecision, he's just making video to brag.

[@KNemo1999]

Merry Christmas, everyone. Bots included.

[@Dexaan]

Bots are people too *beep*

[@angrytedtalks]

🤖 THANKS 😐

[@randallgibson4598]

18k in 12 hours on CHRISTMAS youre fkin killing it bro

[@paulzhu2467]

I personally saw the 5th row as the easiest after placing the first 3 numbers. If we +2 to both sides of the equation we get 9 = _ * 3 + _ . We know 9 is divisible by 3 and _ * 3 is divisible by 3 therefore the number we add must also be divisible by 3. Since 9 and 3 has already been filled in elsewhere, that leaves 6. Filling that in we can get the other space should be occupied by 5.

[@prosperotempest8606]

I was super confused by the first column. Apparently, I have been taking PEMDAS too literally, because if you do the multiplication before the division, you get 8.875=7

[@chiju]

Bro, me too 😭

[@larryrobx]

@@chiju Same.

[@HeavyMetalMouse]

As mentioned above, Multiplication and Division are on the *same* priority level. Similar for Addition and Subtraction. So it's more accurate to thing of the acronym as PE(MD)(AS). There's no inherent priority to MD or AS. The acronym just is easier to make look like a word if you write them in that order. Also also, PEMDAS is not a mathematical law. It is a *convention of notation*. Nothing about the operations as defined require them to be done in any specific order, and Parentheses aren't an operation in themselves - they're a notational device to tell the reader which operations are grouped and should be evaluated first before putting into another operation, by definition. The convention of using that ordering of priorities means that you can write expressions that need to be evaluated without needing a bunch of extra parentheses, and that is honestly its only real use; it makes writing out arithmetic expressions take less effort, in exchange for remembering a priority rule. In mathematics beyond arithmetic, PEMDAS as a device is almost completely irrelevant and absent. If there is *any* chance that you are writing something that isn't clear in the priority of evaluation, you take the extra few keystrokes to *make* it clear. You are never presented a potentially ambiguous statement as a problem and told to resolve it; the notation solely exists to facilitate meaning, not to create puzzles of potential ambiguity. The only time that Order of Operations as a device for resolving expressions becomes relevant again is in Computer Science and Programming, because computers don't have any idea what priority operations have unless someone tells them. So whomever had to write the Math Library for your language of choice had to implement a specific 'order of operations' rule and you need to thus know whatever rule it was they implemented (or else make heavy use of extra parentheses just in case, which isn't a bad idea anyway) - this rule is *usually* some variation of PEMDAS, but check your documentation to be sure!

[@NerdByAnyOtherName]

Assuming this is actually a problem that was posed to a student(s), I imagine the frustration likely came from some combination of not understanding order of operations and not fully applying the established rules (only numbers 0-9 and only once each) Order of operations is something that parents especially are prone to screwing up, and so if the student also only recently learned about them or just generally isn't good at them then I can easily see it being a point of frustration with things not adding up And not fully factoring in the sudoku-esque rule can lead to all sorts of confusion There is also the fact that the logic strategy of "look for and solve the easiest/simplest element first, then follow the new information to solve step by step" isn't readily apparent to small children and/or parents who have been out of school a while and don't regularly engage in logic puzzles. So there is a significant chance that a big part of what got them stuck is that they were looking at the entire problem and suffering from analysis paralysis

[@laszloliptak611]

Nice and fun problem. At 4:00 it would be more accurate to say that "every row and column that is missing a number is missing AT LEAST 2 numbers," as the columns are missing three numbers.

[@Max_Griswald]

Yeah, I was going to point it out, but you got to it first!

[@fifiwoof1969]

7:50 should at least check last row.

[@horstschattenhirn9081]

at 6:51 for the first row you don't have to check for numbers other than 1 and 7. Since 1 is the lowest number, the result for the left hand side of the equation is 4 or bigger, thus the missing number for the right hand side of the equation must be 7, 8 or 9. Since 8 and 9 are already taken at this moment, the missing pair must be 1 and 7.

[@matthewryan4844]

Just a tip, you can double check by looking at the equation going across at the end. 7 = 15 -6- 2 is correct

[@williamboehler5119]

So, did anyone else check the entire puzzle first to make sure it followed the order of operations?

[@SteliosAbahapos]

The kids I know would certainly start from the first row, pick two random numbers and then try to solve the whole puzzle with this assumption. They would give up after a while.

[@firstname4337]

so many bots in the comments

[@henrysaid9470]

so many bots in the comments

[@sans1331]

so many bots in the comments

[@hikari1690]

so many bots in the cements

[@undercoveragent9889]

Thank you for your uplifting and creative observation.

[@wongcheehen-un7dr]

5:56 you can skip the experimenting by 4+5x-y=6 4+5x=6+y and since y is 9 at max x=1,2

[@4p_y]

Thats one hell of a diabolical teacher

[@henrygreen2096]

I paused a bit too early and 'accidentally' ended up using each number 1-to-9 once and now I wonder if the solution is unique for positive integers or not. Is the statement 'use each number 1 to 9 once' a restriction or a hint. My method was probably the most inefficient one. I set each row and column as a separate equation. so you end up having 10 equations with 9 unknowns but you can just throw out the one equation entirely (look at the right most column, no variables. Just a true math statement). Honestly takes probably same amount of time as the video.

[@ashleylentz2651]

after clearing 3, 4, and 9, i next focused on the last row. i added 7 + 2 to get 9, meaning the second unknown number would have to be a multiple of 3 as the product of the first unknown number and 3 is a multiple of 3 and 9 is also a multiple of 3. since 3 and 9 are already off the table, the only option that fits is 6, and figuring out that 5 has to be the first unknown number follows from the fact that 9 = 15 - 6, and 15 = 5 * 3.

[@snowykoyuki]

Stumped parents? Come on it wasnt difficult

[@qqma4791]

Immediately looked at the thumbnail and didn’t realise you had to use digits 1-9. I ended up using -3 and 3 for row 1, 0 and -2 for row 3, 9 and 3 for row 5, 4 for row 7, 7 and 12 for row 9 after setting up a bunch of simultaneous equations. Did I just find another solution that doesn’t use numbers 1-9 with no repetitions? Doing the puzzle with no restrictions is actually more difficult. After realising I could only use digits 1-9 from actually clicking on the video, I found the intended solution in like 2 minutes.

[@Neodynium.the_permanent_magnet]

If you start by solving the 1st column, you get ½x = 2 Fractions are probably difficult at that age.

[@IHateUniqueUsernames]

After sorting out 4, 9, 3, and tried the multiple of 5 for easier elimination, one notices the bottom row enforces and even+odd pair. Since you already figured out where 2 and 8 are, the bottom row must be 5 and 6. This leaves 1 and 7 which are easily confirmed.

[@ninjahotdog9036]

Didn’t see the rules since I solved from the thumbnail, but when looking at the picture I decided that there was no way students could be expected to solve the problem with so few parameters. I counted the amount of empty squares and got 9 which confirmed to me logically that each digit was supposed to be used once, I filled the box in the row with only one empty square, and used process of elimination for the rest.

[@TakacsJanos]

The problem is with the first column. 9 - 4/32 = 7 is obviously false.

[@__-1234]

Even though I find it rather easy, for kids around 10-11 y.o. and parents untrained to reasoning I can understand this is challenging.

[@kenmore01]

Now, do it in 3 seconds.

[@timturner7609]

Lol. The parents bring shame to their ancestors

[@kestrelwings]

For some strange reason, I guessed at every number and got it right the first time. I didn't know that columns needed to match; I just looked at rows. I started with the number 1 which implies 7 to its right. For all multiplications, I chose the smallest number. If my first guess had been wrong, I would have gone back and analyzed things.

[@christopherg2347]

This is just the math version of a Crossword puzzle. You should be able to solve at least part of a Crossword puzzle.

[@gafjr]

I used to love these kinds of problems in grade school.

[@muhammedmitha]

I think the kid was in tears because this simple problem stumped the parents! 😂

[@alexmays6965]

This is just sudoku but math.

[@JensGulin]

Not in the sense that sudoku only have each digit once per column, because col 1 has two 4. Not sure if you meant "just" as a simplification or a trivialization, but I disagree with both. Approaching a grid problem sequentially from the easier parts is a good strategy and valuable hinting to both kids and stumped parents.

[@purplealarmclocker]

Very good logic problem. I’d enjoy this for a homework assignment.

[@chrilaur1143]

Left a kid in tears and everyone stressed as hell? People really need to get some perspective on their lives. If this is the biggest problem you have in your life, then I’d say you’re doing pretty well.

[@sub-harmonik]

I can see how that would be difficult for a 10 year old.. have they even learned algebra by 5th grade?

[@grgfrg7]

Isn't this just the app I keep getting ads for

[@RmNrIHRoZSBDQ1AK]

Fifth grade, are you kidding me? There's no hope left for our species.

[@ayeflippum]

What do you mean?

[@concerned9890]

Not with that attitude

[@Naymy]

I think people were getting stumped at the end and that was what was causing the issue. 7 = 8 - 3 - 4 + 6 but 6 + 4 - 3 - 8 = -1 (that is at least my theory, because I got to the same result and was like "Hang on a second...")

[@ayeflippum]

I tried using simultaneous equations by hand. This didn't work. I then used the simultaneous function in my TI-89 and got a result of "singular matrix".

[@imacatperson432]

Flex: Solved it in under 5 minutes

[@mikesarno7973]

Easy problem for adults to solve. Fun, but not difficult.

[@its_fzx5275]

this looks like suduko even the exact technique of solving but still too hard for the average 5th grader

[@GourangaPL]

Took me few minutes but here's my deduction: First of all in 1st column it's obvious 4. Also 3rd column is obvious 9. From that in 3rd row we have 8-5 = 9-3x2. Now 2nd row if you move 4 to the right you end up with _x5 - _ = 2, so a multiple of 5 always ends with 0 or 5 so to get 2 you need to substract 3 or 8 but 3 was already used so it's 8. From that we see 2nd row is 4+2x5-8=6 Now top row, if you move numbers around a little you see on the left it can only be 1,2 or 3 and on the right respectively 7,8 or 9 but 8 and 9 are already used so 1st row is 9+1-6 = 7-3 From there in 4th columnt we see 6 in the end and we're left with bottom row as 7 = 5x3-6-2

[@domosautomotive1929]

One the difficulty scale of 1-10, I give that a 1.00001. Therefore, those parents are idiots.

[@karthikeyank132010]

Not idiots. Just impatient.

[@skandragon586]

i would give it closer to a 1.5, just for the daunting presentation and that you need to know order of operations. Super easy

[@GuanoLad]

If you don't know to start with the 'one blank' lines, and also don't know order of operations, and many people have forgotten that kind of stuff after thirty years away from school, then it would be intimidating.

[@DrFunkman]

They might have looked at the column and gotten confused. Like damn, the puzzle master must’ve been smoking crack when they wrote 3x6-2x8=2

[@grolfe3210]

I am sure that your opinion will be most helpful to them! I have taught adults in basic maths classes, and would guess that perhaps 30% of adults would not be able to do this as they may not know the order of operations or cannot unpick the problem. Many people have problems with maths and many more have circumstances that deny them a good or even a basic education. On (not one) a scale of difficulty (not the) from 1 to 10, I would rate the problem as 1 ("that" is not clear and the .00001 just silly). (Now you have introduced it as being your view by the "I give", so this should continue with) I therefore think that those parents are idiots. Or better still just keep it flowing in one sentance "With what I would rate as a 1 out of 10 on a difficulty scale, I would conclude that the parents are idiots." I know many people struggle with basic English and so hope this helps. 😀

[@chiju]

Allow me to demonstrate my ignorance. Obviously only 4 works in the fourth row, but then the first column becomes 9 - 4 / 8 x 4 = 7 Order of operations is that we multiply, then divide, so we have 9 - 4 / 32 = 7 9 - 1/16 = 7 But nine minus one sixteenth is not seven. What am I missing?

[@henrygreen2096]

when you re-write the equation like this using the bar instead of the division symbol you must remember the FIRST and only the FIRST integer to the RIGHT of the bar is UNDER the bar. so it looks like: 9 - 4/8* 4 = 7 *many ways you can do the next step, Easiest is to simplify* 9 - 1/2*4 = 7 *now multiply ACROSS* (1/2)*(4/1) = (1*4)/(2*1) = 4/2 = 2/1 = 2 9 - 2 = 7

[@chiju]

@@henrygreen2096I get it now, thank you.

[@haddysrosserrier2061]

it's basic algebra written in a sudoku form.

[@MsAcpaul]

Good puzzle, definitely appropriate for grade 5. Sometimes I think parents are helping their child with their homework find it too hard, hence their child gives up at the same time. On the other hand if no problem solving is taught in the classroom especially previous years it can be harder for students to independently have a positive go. Presh I commend you for your explanation in the video. It's presented with minimal algebra and easy to follow for that age group.

[@SuperCrAzYfLiPpEr]

I found it easier to solve the multiplications and divisions where for example 4+5x-y=6 and x=(2+y)/5 and then checking for which number y of 2+y is divisible by 5.

[@vinodvenkatesan]

What tool do you use for your animations? Thanks

[@robertolson7304]

It's not a math problem. It's a logic problem. Do school off logic studies? Nope. So why is it in math.

[@hugohabicht6274]

That was super simple, what kind of parent struggles with this?

[@karthikeyank132010]

Did you pause the video and solve it yourself before MindYourDecisions showed the solution?

[@skandragon586]

@@karthikeyank132010 i did, and it only took a few minutes

[@ArliyoSidow-vv1mw]

6:31 "six plus another number is equal to another number" um yea id think?

[@soundsoflife9549]

Doesn't the first column equal 1?

[@barttenbrinke2155]

Eeh, the first column does not add up ?

[@blackenedmagic888]

Using the order of operations you have: 9 - ((4/8) x 4) = 9 - ((1/2) x 4) = 9 - (2) = 7.

[@johnmorriss5308]

@@blackenedmagic888 But who says a vertical equation is evaluated top to bottom? No OOP that I've ever seen even mentions it, because it's not a thing...

[@discountchocolate4577]

Left-to-right rule (or top-to-bottom) for multiplication and division is assumed here. "4 / 8 * 4" is interpreted as equivalent to (4/8)*4, which is 2.

[@chiju]

Why is it not 9 - (4/(8x4)) = 9 - (4/32) = 9 - (1/16) = 8 15/16? Don't you multiply before you divide?

[@blackenedmagic888]

@@johnmorriss5308 Yeah, you are technically correct, but you're also splitting hairs big time. Think on this: the vast majority of languages are written and read from left to right, but there are many exceptions (such as Arabic and Hebrew) that are written in the opposite direction. However... to the best of my knowledge, there is not one language which is written and read from the bottom of a page towards the top. Thus, logic dictates that a vertical equation should be evaluated from top to bottom.

[@rosellelisondra8249]

Fun fact: as of now Dec. 26 the number of Mind Your Decision's subscribers is now Pi.

[@JensGulin]

That's irrational. Pi millions, more like it, but still an approximation.

[@ABhaim]

(PAUSED) constructed the equations and came up with 3 instant solutions for 4, 9, and 3. Then, as I was about to construct a 6 by 6 matrix for the other variables, I thought I'll approach it logically and did it. Came up with (row wise) 1, 7, 2, 8, 9, 3, 4, 5, 6 (UNPAUSING) I took the first row as the next step , as there are only 3 options for numbers below 10, which one of them is greater than the other by 6.

[@mihailghinea]

6:27 better to start with 2nd column, I think.

[@raphaelchan7574]

This is kind of like sudoku tbh

[@JHgamer7391]

this was a nice way to wake up

[@DarshRaniga]

wait first column doesnt work

[@mattdevico5747]

I can't get column 1 to equal 7, regardless of order of operations (assuming the digits provided by the video are correct).

[@derekparsons4]

Glad you said this. Me neither. I don't think it works.

[@reldahr01]

That was a good one. Sudoku + Algebra

[@AK-fu8ij]

if you cant solve this puzzle you should not be having children. sorry.

[@SillyGooseGracie]

Hello Fresh Tall Walker! I got one of your math puzzle books for Christmas! Unfortunately I am not as smart as I thought I was and am having trouble solving most of them, but I love it anyway!

[@Noneya-bw5gm]

Seems pointless. Can anyone point to a real world application of this exercise? Math education has always been a case of people with advanced degrees trying their best to frustrate young children and destroy their interest in math.

[@johnmorriss5308]

There needs to be one more rule: Apply the order of operations from left to right in a row, and from top to bottom in a column...

[@Cobb]

Started without knowledge of only using each number once but got it in the end, though it took a while, 4th row is solved first with 4, then 3rd column with 9, 4th column with 3. 5th row was a guess but worked out with 5 and 6, then the columns 2 and 4 were both x=y-1, so column 3 went with 1 and 2 and column 4 was left with 7 and 8.

[@NoProductionsGD]

reminds me of the ab × c = de + fg = hi problem

[@thusithawanigasinghe-gd1nj]

How is this even hard?This is way too easy.

[@MrShikaga]

I am guessing you haven’t spent much time teaching a classroom of 10 year olds. Some will get it, but I dont think it is fair to say it is too easy for the whole class.

[@thusithawanigasinghe-gd1nj]

@MrShikaga Listen I'm no teacher and I can understand why that kid is saying it's difficult.But how can the parents can't understand it?

[@Mrgreenhippo1]

I love cross nerdles.

[@KiloOscarZulu]

9 unknowns and 9 equations - has anyone solved it with matrices?

[@tobyfitzpatrick3914]

That's not till 6th Grade..!

[@KiloOscarZulu]

@@tobyfitzpatrick3914 I'm an engineer, so we have to use matrices somewhere.

[@MLWJ1993]

This looks like a fun exercise! Would've made me very happy as a kid.

[@situational.analysis]

I like it. Neat layout and not too difficult.

[@AJCrimson608]

9-4÷8×4=7 (first column) is what I'm struggling with. Even read bottom to top as 7=4×8÷4-9, it makes no sense.

[@JensGulin]

You read from top, and order of operations treat division and multiplication (left to right) before subtraction. 9-( (4÷8) ×4)=7 The tricky part is that division needs to go before the multiplication, which gives you 1/2, that may feel strange, but multiplied with 4 it's just 4/2 or 2. 9-2=7 That's ok, right? If you want to live by PE[MD][AS], it's important to relearn that within the brackets, order follows left to right in the equation. If you take multiplication always first, in this case the equation breaks indeed.

[@deadrosesforall]

congratulations dude youre at 3.14m subscribers

[@natviolen4021]

That is a nice and funny puzzle. Why did people struggle? Because they couldn't find a method to solve it? Because they didn't follow the order of operations? Or?

[@LocksVid]

I took so long to do it because I was thinking the solution just work in all 4 directions, the question should be explained more clearly

[@natviolen4021]

@@LocksVid I see. I often play sudoku, maybe that's why I got it right away.

[@jonnyreb3032]

I pulled this up missed the instructions and still solved it...after trying to go algerbraic substituion and relizing there were too many variables I tried trial and error

[@miguelflores4416]

Just start solving with the 8

[@DK-xd7pb]

Now solve it by allowing fractions and negative numbers :)

[@cicirocirocicirocirera]

this is such a fun homework, would like if my teacher made this a homework lol

[@marvhollingworth663]

I paused it & quickly got the 1st 3 numbers, but then I was stumped for a bit. So I unpaused it & found each number could only be used once - I'd paused it too soon. Once I knew that, it was easy but I did the bottom row next. The 1st unknown had to be a 5, which made the other unknown 6. Then I did the 2nd column & the top 2 rows. Completely different order but got the same answer. Oh & I got the 1st number by doing column 1, not row 4.

[@sansstuffOG]

Right now the sub count is at 3.14!! It’s Pi

[@ahmed_elfayoumy2782]

3.14M subs!!! NICE!!

[@ahmed_elfayoumy2782]

PI

[@MohamedArtimA]

Quiz💡 +7 -8 = 💡سهل