• edgemaster72@lemmy.world
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    8 months ago

    0.5 / 0.5 = 1, so reducing the top term by half (from 0.5 to 0.25) reduces the result by the same (from 1 to 0.5), makes perfect sense to me. Or, ya know, just remember that dividing by 0.5 is the same as multiplying by 2.

  • afraid_of_zombies@lemmy.world
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    8 months ago

    If you move it around it makes more sense.

    .25 = 0.5*0.5

    If you take half of something only half of the time you take a quarter of something.

  • SkyNTP@lemmy.ml
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    8 months ago

    Dividing by a division of 2… Of course it’s going to cancel out. Like subtracting a negative.

    Surely you don’t not understand double negatives? Just think of it like that.

  • Leviathan@lemmy.world
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    8 months ago

    Maybe someone better at math can answer this, but is 0.25/0.5 functionally the same as 0.5/1, or simply 0.5?

    • doctordevice@lemm.ee
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      8 months ago

      You can call it whatever you want, as long as it equals 1/2 it’s the same number.

      So yes, multiplying by 2/2 to make it more intuitively obvious is perfectly valid and a good way to think about it. Most arithmetic tricks are ultimately multiplying by 1 or adding 0 just to make the problem easier to handle.

      • Leviathan@lemmy.world
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        8 months ago

        Oh yeah, I just meant that they said I multiplied by 2, which in my head is 2/1 but I was multiplying by 1. Just trying to be clear.

    • 𝕾𝖕𝖎𝖈𝖞 𝕿𝖚𝖓𝖆@lemmy.world
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      8 months ago

      I think it’s easier to picture it in terms of fractions. When you divide by a fraction, you reciprocate the divisor. That is, you flip its numerator and denominator, then multiply them. In this case, we’re taking 1/4 and dividing it by 1/2. You take the reciprocal of 1/2, which is 2/1. Then multiply the numerators and denominators. You end up with (1/4)*(2/1)=2/4=1/2=0.5

    • intensely_human@lemm.ee
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      8 months ago

      I cannot comprehend how bad at math you need to be to ask this question.

      Like, 2 + 2 = 4 = 3 + 1.

      These are all equivalent. That’s what this symbol means: =

      • crapwittyname@lemm.ee
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        8 months ago

        There are better ways of saying this. You know, polite ways, where you don’t come across as an insecure dickhead.

      • SoleInvictus@lemmy.world
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        8 months ago

        I cannot comprehend the level of douchery required to mock someone for asking an honest question. It’s gotta be high, at least Summer’s Eve or beyond.

        The best part is how your answer is bad. It’s a correct statement but it doesn’t answer their question.

      • recapitated@lemmy.world
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        8 months ago

        That is really mean. You shouldn’t attempt to teach people anything if this is what your mindset is like.

  • TxzK@lemmy.zip
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    8 months ago

    0.5 = 1/2, 0.25 = 1/4

    0.25 / 0.5 = (1/4) / (1/2) = 1/4 * 2/1 = 2/4 = 1/2 = 0.5

    • raspberriesareyummy@lemmy.world
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      8 months ago

      y/x = x with y = x*x because 0.25 is 0.5 squared.

      from the “wow factor” it’s the same as writing: 9/3 = 3 - not very wow at all

    • AFK BRB Chocolate@lemmy.world
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      8 months ago

      Start with the reverse. If you had half a pizza and you wanted to divide it by quarters of a pizza, you’d be able to do it 4 times (there are four quarter slices in a half pizza).

      But with this we’re asking how many half-pizza slices are in a quarter-pizza slice. The answer is that there’s half of one (half of a half is a quarter).

    • myxi@feddit.nl
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      8 months ago

      you’re just doing 1/2 in a smaller scale. it makes most sense logically; it’s actually the numbers that are confusing you.

  • recapitated@lemmy.world
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    8 months ago
    • 250 marbles / 500 kids = 0.5 marble per kid
    • 25 marbles / 50 kids = 0.5 marble per kid
    • 2.5 marbles / 5 kids = 0.5 marble per kid
    • 0.25 marbles / 0.5 kids = 0.5 marble per kid, but there’s only one half a kid with a quarter of a marble in this example.
  • Iron Lynx@lemmy.world
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    8 months ago

    In case people would like it demonstrated,

    0.25/0.5

    = 1/4 ÷ 1/2

    = 2/4 ÷ 2/2

    = 1/2 ÷ 1

    A÷1 = A, therefore 0.25/0.5 = 0.5

    Alternatively, (a/b)/(c/d) = (a×d)/(b×c)

    1/4 ÷ 1/2 = 1×2 ÷ 4×1 = 2/4 = 1/2

    • Iron Lynx@lemmy.world
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      8 months ago

      And before any pedants crawl out of the woodwork, there are a load of implied brackets, at the spaces.

  • vampire@lemmy.world
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    8 months ago

    Every time I see something like this, the comments remind me that common core mathematics is a thing and it makes me sad.

    • doctordevice@lemm.ee
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      8 months ago

      Seriously, why is basic arithmetic worthy of so much discussion?

      Just… do the math. It’s not complicated math.

      • vampire@lemmy.world
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        8 months ago

        I sometimes feel bad about myself cause I didn’t get very far into calculus, but then I remember that the average adult has no idea how fractions work.