• Crowfiend@lemmy.world
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    5 months ago

    It only signifies that the post-decimal nines are repeating infinitely. It still doesn’t make 99.99999…=100 unless you intentionally round the value for some nondescript reason, and even then, rounding off isn’t changing the value, only the perceived value for mathematical simplicity, not objective accuracy.

    • chiliedogg@lemmy.world
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      5 months ago

      “.9…” is repeating, but rational. So it’s actually “1” . Let’s do the math.

      .9… / 3 = .3…

      .3… = 1/3

      1/3 x 3 = 3/3

      .9… = 3/3

      3/3 = 1

      .9… = 1

      Still not convinced? We’ll use algebra instead of fractions.

      0.9… = x

      10x = 9.9…

      10x - 0.9… = 9

      9x = 9

      x = 1