• MotoAsh@piefed.social
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    6 months ago

    Hopefully you can see where their confusion might come from, though. PEMDAS is more P-E-MD-AS. If you have a bunch of unparenthesized addition and subtraction, left to right is correct. A lot of like, firstgrader math problems are just basic problems that are usually left to right (but should have some extras to highlight PEMDAS somewhere I’d hope).

    So they’re mostly telling you they only remember as much math as a small child that barely passed math exercizes.

    • DefederateLemmyMl@feddit.nl
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      6 months ago

      If you have a bunch of unparenthesized addition and subtraction, left to right is correct

      If you have a bunch of unparenthesized addition and subtraction, left to right doesn’t matter.

      1 + 2 + 3 = 3 + 2 + 1

      • KubeRoot@discuss.tchncs.de
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        6 months ago

        If you have a bunch of unparenthesized addition and subtraction, left to right doesn’t matter.

        Right, because 1-2-3=3-2-1.

          • KubeRoot@discuss.tchncs.de
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            6 months ago

            I did not flip any signs, merely reversed the order in which the operations are written out. If you read the right side from right to left, it has the same meaning as the left side from left to right.

            Hell, the convention that the sign is on the left is also just a convention, as is the idea that the smallest digit is on the right (which should be a familiar issue to programmers, if you look up big endian vs little endian)

            • howrar@lemmy.ca
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              6 months ago

              If that’s your idea of reversing the order, then you’re not talking about the same thing as SpaceCadet@feddit.nl. They’re talking about the order of operations and the associativity/commutativity property. You’re talking about the order of the symbols.

            • I did not flip any signs

              Yes you did! 😂

              merely reversed the order in which the operations are written out

              No, merely reversing the order gives -3-2+1 - you changed the signs on the 1 and 3.

              If you read the right side from right to left, it

              Starts with -3, which you changed to +3

              it has the same meaning as the left side from left to right

              when you don’t change any of the signs it does 😂

              Hell, the convention that the sign is on the left is also just a convention

              Nope, it’s a rule of Maths, Left Associativity.

      • MotoAsh@piefed.social
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        6 months ago

        True, but as with many things, something has to be the rule for processing it. For many teachers as I’ve heard, order of appearance is ‘the rule’ when commutative properties apply. … at least until algebra demands simplification, but that’s a different topic.