• FiskFisk33@startrek.website
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    4 days ago

    That’s because multiplication is commutative

    taking a percentage of something essentially means multiplying it with a hundreath of the percentage
    6% of 50 essentially means 50 * 0.06
    or 50 * 6 * 0.01

    and since
    50 * 6 * 0.01 = 6 * 50 * 0.01
    then of course
    50 * 0.06 = 6 * 0.5

    And we have the above

    • LifeInMultipleChoice@lemmy.dbzer0.com
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      4 days ago

      Yeah my brain just sees 5*6, and then I move the decimal. I never understood how people couldn’t figure out tips when they wanted 20%.

      If you live in the U.S. you do them quite often, multiply by 2. Want 10 multiply by .1… Half that and add it if you want 15. Whatever is easiest at that moment

    • ricecake@sh.itjust.works
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      4 days ago

      I prefer to keep it technically correct yet evil and confusing. 6% being a fancy way to write 0.06 or 6 * 1/100 means we can take 6 * 50 * 1/100 and simplify to 300 * 1/100 and then represent that as 300%.

    • Johandea@feddit.nu
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      4 days ago

      … in 1 or 2 dimensional number systems, also known as the real (1-dimension) and the complex (2-dimensions) numbers. With quaternions and higher dimensional systems multiplication is not communicative. In fact, the more dimensions you add, another mathematical property is lost.

      • TheTechnician27@lemmy.world
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        4 days ago

        … okay? Yes? Nobody thought otherwise? Do we now have to clarify every statement about algebra by specifying that we’re talking about an algebra over the reals or the complex numbers? Or the polynomials or the p-adic integers, whose multiplications are also commutative?

        No one would call these “n-dimensional” number systems either. The algebra for each of these operates in R1 and R2, respectively, but, like, you would describe their algebras as being over an n-dimensional vector space. It’s not wrong, but I don’t think “two-dimensional number system” is something you’d hear mathematicians say.

        This pedantic aside feels so “I just watched a 3blue1brown video and feel verysmart™” that I don’t know what to do with it. It’s good to be interested in math, but this ain’t it. Everyone knew what they meant.