this post was submitted on 03 Dec 2023
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The correct answer is 16. Multiplication and Division happen at the same level of priority, and are evaluated left-to-right.
No it's ambiguous, you claiming there is one right answer is actually wrong.
It is not ambiguous at all, there absolutely is one right answer, and it is 16.
You're taking something you learned when you were like 9 years old and assuming it's correct in every situation forever.
Unfortunately this isn't the case and you're incorrect.
Inaccurate, this has nothing to do with the mnemonic PEMDAS, this has to do with the actual order of operations it tries to instill. That order of operations is not ambiguous, there is a correct way to solve simple equations like the one above, and there is one and only one correct answer to it. That answer is 16.
And in the "actual" order of operations, if we want to pretend one exists,
2(binds more tightly than÷if you're going via prescriptivism, then you're wrong, because there are plenty of authoritative sources following the left hand model
if you're going via descriptivism, then you're wrong, because this thread exists
No, 2( does not bind more tightly than ÷. 2( is simply 2×(..., and ÷ and × occur at the same level of priority. After resolving the addition in the parentheses, the remaining operations are resolved left to right.
No it isn't. 2(a+b)=(2a+2b) The Distributive Law
No, the fact that a good many people are incorrect about how math works does not entail that math is an open question. It's not, math has actual rules to its equations and an unambiguous right answer. In this case, that answer is 16.
you know you could've just started this by admitting you've never touched the subject at a higher level than high school and saved us all this bother
I'm well familiar with math and the rules by which it works. Those who persist in arguing the case here could save the rest of us the bother by admitting they were stumped by a simple gotcha equation and are embarrassed, rather than wasting everyone's time by insisting that math is nothing but a lawless, rules-free wasteland where the answer to an equation depends on your feelings at the time.
i know you won't realise this because you never got past basic calculus, but this is a very funny statement to anybody that did
they know all the "math rules" guys. which ones? ALL of them
but okay these rules: where do they come from, then?
Fortunately, the rules necessary to resolve the equation in this post are extremely elementary, so none of what you're referencing has any bearing whatever.
There are exactly three things to consider in here to determine priority: parentheses, multiplication/division, and addition. The addition happens first due to the parentheses, and the remaining is evaluated left-to-right. The only correct answer here is 16.
All your deflection from your embarrassment at misreading a simple equation doesn't detract from this.
this would be like trying to tell a chemical engineer they didn't know what they were doing based on your understanding of the atom as a ball of protons with electrons wooshing round it like they were moons
very cute
unfortunately, if you give the expression
1 / 2xto anybody who knows what they're doing they'll interpret it as1 / (2x)because it would be absurd not tofor reference, that's why the calculator works like this. because it's a tool designed primarily for people who actually know what they're doing with numbers, so it works how they expect it to work
And there you've proven exactly what I've been saying all along. 2x works the way it does because there's a variable involved, and natural reading of that treats it as a single entity. There are no variables in the equation in the post, there are only definite numbers, parentheses, and simple mathematical operations. 8/2(2+2) is nothing more than 8/2×(2+2). There is nothing special about 2(..., this is not the equivalent of 2x.
Just like 2(2+2) is also a single Term.
Pronumerals literally stand in for numerals, and work exactly the same way. There is nothing special about choosing a pronumeral to represent a numeral.
They're completely different actually. 2(2+2) is a single term in the denominator, (2+2) - which you separated from the 2 with an x - is a now 3rd term which is now in the numerator, having been separated from the 2 which is in the denominator.
So what's it equal to when x=2+2?
a natural reading of
2(2+2)treats it as the sameyou're straight up just spouting contradictory nonsense now because you've realised your stance doesn't make any sense, and i am very much here for it
No, what I'm explaining to you is the facts behind what every calculator with any modicum of computing power will tell you, namely that 2(2+2) is identical to 2×(2+2).
ah yes it's the computing power that's at issue here
Yeah, kind of. The crappier calculator is the one generating the incorrect answer. Any calculator with any real level of oomph behind it can parse this correctly to get the correct answer, 16.
~ local galaxy brain
The good calculator is the one using the processing power of the phone to handle the programming necessary to correctly interpret the order of operations and arrive at the correct answer, whereas the bad calculator - despite having no ads - is a cheap piece of trash unable to contain the necessary computational logic to arrive at the correct answer.
try again
No need. The fact that you're incapable of comprehending it at this point indicates that any further attempts to explain it to you are equally likely to fall on deaf ears.
Which would be the app written by the programmer who didn't check his Maths was correct, as opposed to the calculator made by a company who, you know, makes calculators.
But there actually is only 1 right answer, and unfortunately for the person you're replying to it's 1.
PEMDAS be damned?
PEMDAS should be read as Parentheses, Exponents, Multiplication and Division, Addition and Subtraction. There are four levels of priority, not six.