• billwashere@lemmy.world
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    7 days ago

    If you increase something by 10% you’re doing this:

    (10% • X) + X

    (.1 • X) + X

    1.1 • X

    So you’re just multiplying the original value by 1.1. Similarly for subtracting 10% you’re multiplying by .9

    So the order in which you add or subtract 10% doesn’t matter. You always get the same number.

    • Ostrakon@lemmy.world
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      7 days ago

      I have 100 dollars. I lose 10% of it. I now have 90 dollars. Now I increase my 90 dollars by 10%. Is it your assertion that 10% of 90 is 10?

      • billwashere@lemmy.world
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        7 days ago

        No. Because increasing 90 by 10% is:

        90 • 1.1 = 99

        Percentage is relative to current value, not previous calculations. 10% of 90 is 9.