this post was submitted on 12 Dec 2023
849 points (96.4% liked)

Memes

45727 readers
1034 users here now

Rules:

  1. Be civil and nice.
  2. Try not to excessively repost, as a rule of thumb, wait at least 2 months to do it if you have to.

founded 5 years ago
MODERATORS
849
6÷2(1+2) (programming.dev)
submitted 11 months ago* (last edited 11 months ago) by wischi@programming.dev to c/memes@lemmy.ml
 

https://zeta.one/viral-math/

I wrote a (very long) blog post about those viral math problems and am looking for feedback, especially from people who are not convinced that the problem is ambiguous.

It's about a 30min read so thank you in advance if you really take the time to read it, but I think it's worth it if you joined such discussions in the past, but I'm probably biased because I wrote it :)

you are viewing a single comment's thread
view the rest of the comments
[–] Perfide@reddthat.com 8 points 11 months ago* (last edited 11 months ago) (28 children)

You lost me on the section when you started going into different calculators, but I read the rest of the post. Well written even if I ultimately disagree!

The reason imo there is ambiguity with these math problems is bad/outdated teaching. The way I was taught pemdas, you always do the left-most operations first, while otherwise still following the ordering.

Doing this for 6÷2(1+2), there is no ambiguity that the answer is 9. You do your parentheses first as always, 6÷2(3), and then since division and multiplication are equal in ordering weight, you do the division first because it's the left most operation, leaving us 3(3), which is of course 9.

If someone wrote this equation with the intention that the answer is 1, they wrote the equation wrong, simple as that.

[–] wischi@programming.dev 22 points 11 months ago (22 children)

The calculator section is actually pretty important, because it shows how there is no consensus. Sharp is especially interesting with respect to your comment because all scientific Sharp calculators say it's 1. For all the other brands for hardware calculators there are roughly 50:50 with saying 1 and 9.

So I'm not sure if you are suggesting that thousands of experts and hundreds of engineers at Casio, Texas Instruments, HP and Sharp got it wrong and you got it right?

There really is no agreed upon standard even amongst experts.

[–] kogasa@programming.dev 6 points 11 months ago (9 children)

Hi, expert here, calculators have nothing to do with it. There's an agreed upon "Order of Operations" that we teach to kids, and there's a mutual agreement that it's only approximately correct. Calculators have to pick an explicit parsing algorithm, humans don't have to and so they don't. I don't look to a dictionary to tell me what I mean when I speak to another human.

[–] fallingcats@discuss.tchncs.de 1 points 11 months ago* (last edited 11 months ago)

Thanks for putting my thoughts into words, that's exactly why I hate math. It was supposed to be the logical one, but since it only needs to be parsed by humans it failed at even that. It's just conventions upon conventions to the point where it's notably different from one teacher/professor to the next.

I guess you can tell why I went into comp-sci (and also why I'm struggling there too)

load more comments (8 replies)
load more comments (20 replies)
load more comments (25 replies)