Post by @bemmesr@mathstodon.xyz

2026-08-02 11:17 UTC

@SmartmanApps@dotnet.social alright ‘smartman’, if there is only one standard for order of operations then why is it that when I put ‘3÷2(6)’ into my #Casio fx-100AU PLUS the answer is ‘0.25’, but when I put the same exact string into my Google Pixel's calculator app the answer is ‘9’? I suppose you'd say my #android is wrong, right? Maybe so, but then you can't deny that the confusion is pervasive. If 72.77% (https://www.sci-tech-today.com/stats/android-phones-statistics/) of mobile phones will tell you the wrong answer in their default app, are we simply to ignore it? Well, again, maybe so. That's the way you would have it, isn't it? If they're wrong they're not worth listening to. But when I write a mathematical expression, I want it to be that no matter who copies it down into whatever calculator, that they all get the same result. To me that would be ideal. And to achieve that, I will use as many brackets as necessary (or I will simply use fraction notation if I can). As for brackets being new, this isn't really an argument. We would expect the language of mathematics to become more standardised, and less ambiguous, over time. In the early days of mathematics we didn't even have standard symbols for any of the arithmetic operators. To begin with, mathematics was the privilege of the educated few, and now days it is a common tool for the common person. With that comes a requirement for intuitive clarity, not knowledge of some standard order of operations (which again, a majority of mobile devices don't even adhere to).

Replies (3)

@FishFace@ioc.exchange 2026-08-02 11:41

@bemmesr@mathstodon.xyz @SmartmanApps@dotnet.social In his eyes, the only sources that are relevant are high school textbooks, and only when they agree with him (Lennes' textbook from long ago did not, but nevertheless exists; if you look into his even whackier ideas like that 0.999... ≠ 1, it's very easy to find textbooks that contradict him. Somehow he manages to continue believing.) I mean for goodness sake, this is the guy who makes a poll which proves that an expression is ambiguous (16% of people selected the variant) and still insists it's unambiguous. For him, ambiguity is purely a theoretical concept, not a practical one. He has written that there is no ambiguity between the meaning of "f(x)" (whether it means f×x or the application of the function f to x) because you just need the additional information of whether f is a function. Well, if we have the additional information of how the writer of an expression with mixed multiplication and division intended it to be grouped, sure, that's unambiguous too. BTW on calculators, one thing I never got him to cough to is that for decades most calculators didn't understand order of operations at all. The Casio fx-110 from 1977 is a good example because it was popular and has an example in its manual.

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@bemmesr@mathstodon.xyz 2026-08-02 11:37

@SmartmanApps@dotnet.social for anyone looking in on this thread who can't see the relevant posts, here's some screenshots:

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@SmartmanApps@dotnet.social 2026-08-02 11:33

@bemmesr@mathstodon.xyz "Google Pixel's calculator app the answer is ‘9’" - programmers who have forgotten the rules of Maths 🙄 https://dotnet.social/@SmartmanApps/111164851485070719 "then you can't deny that the confusion is pervasive" - did you miss the bit where I said confusion on socials doesn't matter one iota? "are we simply to ignore it?" - yep! Just like you should ignore AI. Did you notice the common theme here yet? "they all get the same result" - which, as I said, means you'd have to do it for + and - as well!

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