• ColeSloth@discuss.tchncs.de
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      1 day ago

      it’s very often not useful. Like, what’s 6% of 80? See. Still hard.

      Also, with the 6% of 50 example it’s easy without using this trick.

      What’s 6% of 100? 6, right? So cut 100 in half to get to 50, and cut the 6 in half to get the 3. Cut the 50 in half again and cut the 3 in half again, and you’ll also know that 6% of 25 is 1.5.

      Which also lets you know that 6% of 75 is 4.5. the 3 from the 50, plus the 1.5 from the 25. or just know to split the difference between the 3 at 50 and the 6 at 100.

      A lot of math is just tricks for a thinking process.

      • starik@lemmy.today
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        4 hours ago

        It’s always as easy as multiplying the two numbers. Just convert the percentage to a decimal.

        0.06x80 is just as easy as 0.8x6. It’s just a matter of knowing 6x8 is 48, which quickly gets you to 4.8 here.

      • Atomic@sh.itjust.works
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        18 hours ago

        6% of 80. 1% of 80 is 0.8 0.86 is (86)/10 Which is 48/10 = 4.8

        80% of 6. I’d probably think of it as (4/5)*6 = 24/5 Which is 20/5 + 4/5 = 4 + 4/5 = 4.8

        Both are easy if you know how to visualise it. The benefit of knowing you can “reverse” it is that you can choose which method is easier for you to visualise. Which is incredibly useful for a lot of people

      • ddplf@szmer.info
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        1 day ago

        Good luck explaining your supreme methodology to anyone that isn’t a geek.

        • ColeSloth@discuss.tchncs.de
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          23 hours ago

          It’s stupid simple… If you know 6% of one hundred is 6, then you should know 6% of 50 is 3. You just cut each number in half.