Re “Can You Solve This Vietnamese Math Puzzle for 8-Year-Olds?”

This seems kind of difficult for 8 year olds. Is this really the level of math they are expected to tackle or is this made up nonsense?

Re “Can You Solve This Vietnamese Math Puzzle for 8-Year-Olds?”

This seems kind of difficult for 8 year olds. Is this really the level of math they are expected to tackle or is this made up nonsense?

All the identical articles seem to have started from *The Guardian*.

No source (except the “village of Bao Loc”), but I think it’s real. What’s not real is “Is this really the level of math they are expected to tackle.”

No, some teacher gave it to his/her students, not realizing how hard it was, is my guess.

The Guardian article links to a Vietnamese article and imply that the writer used Google translate for quotes. Google translating it myself I get the impression that it’s an article about an exam problem that someone thought was too hard, and that’s been sent for review and that an official of some sort says that it’s not a problem completely unsuitable for the age group in question, since it relies only on basic arithmetic, but that the difficulty is out of range, being hard even for adults.

Asians taught math at birth. Our placentas are even locked with a math riddle we’re expected to solve before we can be born.

Source: Am Asian

I first looked at it and thought, “Oh, it’s just a simple number train, my 8 year old could probably do that.” Then I realized there was only 1 equals sign and, yeah… no way in hell she could figure this out. Pretty sure she hasn’t learned order of operations or factoring yet. Even then I had to brute force it, didn’t get it right until the 3rd try.

5, 9, 3, 6, 2, 1, 8, 7, 4

I was given puzzles in a similar vein to this at that age range. I had already been taught basic arithmetic with variables (though not that many, to be honest, usually no more than three) and taught the order of operations by this point, so I think given a half hour to solve it, I could have figured it out or come close. These sorts of worksheets were given out for fun at the end of the day though and no points were taken off if you couldn’t solve them. My favorite logic puzzles were the “Who has the fish?” kind though.

So yes, I could see it being possible this was handed out, but not really as an exam question or something serious.

It’s unclear whether we’re supposed to follow order of operation or not. Assuming not (which seems more likely to me given the way the problem is presented), some computer analysis reveals that there are 119 distinct answers, at least if we restrict all intermediate results to whole numbers. All of them involve intermediate results that are at least 3 digit numbers.

Here’s one of the “best” ones, as far as numbers not getting too out of control:

5 8 6 7 1 3 9 4 2

5 + 13 = 18

18 x 8 = 144

144 / 6 = 24

24 + 7 = 31

31 + 12 = 43

43 x 1 = 43

43 - 3 = 40

40 - 11 = 29

29 + 9 = 38

38 * 4 = 152

152 / 2 = 76

76 - 10 = 66

What chain of logic can lead to that for an 8-year-old is beyond me.

This doesn’t work when I try it.

I don’t know about the Vietnamese, but I can tell you the vast majority of Thais absolutely stink at math. The wife is a statistician, and her fellow Thais’ severe lack of numeracy always has her climbing the walls. This meme of Asians being good at math is strictly for the birds.

Assuming only integer results, left to right evaluation rather than PEDMAS, and no negative results (I’m assuming 8 year olds haven’t studied those concepts yet). I’d start like this:

Go backwards from the end result. The last number before subtracting 10 is obviously 76, so what are the single digit factors of 76?

4*19 = 76
2*38 = 76

1*76 = 76

So the last number is either 1, 2, or 4. You then continue with this sort of deduction. I haven’t gone any further yet, so I don’t know how straightforward it is from there. The logical possibilities may grow exponentially from there, or they may not.Of course, that type of reasoning strikes me as being beyond the capabilities of the vast majority of 8 year olds.

Ignore that. It’s completely, embarrassingly, wrong, but the edit window has passed. :o

That in and of itself makes me think that the problem wasn’t really on tests. I can’t imagine having 119 different answers to check against.

[spoiler]a + ((13 * b) / c) + d + (12 * e) - f - 11 + ((g * h) / i) - 10 = 66

5 + ((13 * 9) / 3) + 6 + (12 * 2) - 1 - 11 + ((8 * 7) / 4) - 10 = 66

5 + (117 / 3) + 6 + 24 - 1 - 11 + (56 / 4) - 10 = 66

5 + 39 + 6 + 24 - 1 - 11 + 14 - 10 = 66

44 + 30 - 12 + 4 = 66

74 - 8 = 66

66 = 66[/spoiler]

I think that it may be possible to narrow the search somewhat, although I haven’t completely figured out the process.

I do know, for example, that the total before subtracting the final 10 has to be 76 and the total before the division preceding that has to be a multiple of 76 and some integer value from 1 to 9. (I sort of had that backwards in my previous post.) I’m not sure if that line of thinking is useful or not.

I can’t see why one would present a math problem and not follow the order of operation.

I *might* be able to figure out the problem, given an hour or so. I decline to believe that Viet Nam has a population of eight year olds who can routinely solve it. I suck at math, but I suspect so do most eight year olds, no matter the nationality.

Regards,

Shodan

Regarding order of operation, have eight year old Vietnamese children even been taught that yet?

To me the layout seems to imply a straight left to right order, but I could be mistaken.

It seems like trying to follow PEDMAS makes the problem much more difficult and it’s already difficult for 8 year olds.

I have no idea. What I mean is the idea of saying ‘solve this problem but don’t apply the rules’ is bad teaching.

I concur. Which is one of the reasons I disbelieve that this is the kind of math problem Vietnamese 8 year olds are expected to solve, no matter what *The Guardian* claims.

Regards,

Shodan

As an interesting side note; there are a number of “trick question” graphics floating around FaceBook (and probably other places) that consist of strings of numbers connected by arithmetic operations and asking people to solve them. They’re trick questions in the sense that they depend on PEDMAS to get the right answer. There are always a number of people, including adults, who simply proceed left to right and, from the conversations, appear to have no concept of the proper order of operations.

Order of operation is a convention about how to group mathematical operations when they are written out. They’re only a convention, and only apply in some contexts. And the graphical treatment of the snake-shaped numberline at least seems to SUGGEST not to use them.

In other words, we need more information, or someone who is familiar with how math is taught to 8-year-olds in Vietnam, to really get an answer.

Regardless of whether or not order of operation rules are used, it seems too difficult for 8 year olds, unless they think the busy work of trying all combinations is somehow educational.

Come to think of it, maybe a communist country wants to raise a generation of people accustomed to repetitive mind-numbing tasks.