• TWeaK
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      1 year ago

      PEMDAS is what they teach school children to help them learn. Like most such rules, it’s oversimplified and doesn’t quite work all the time.

      The proper way is to write a fraction top and bottom. Thus, 8(2+2) / 2 = 16, while 8 / 2(2+2) = 1. The implicit multiplication simply does not work if they’re split across the fraction.

        • TWeaK
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          1 year ago

          Replace (2+2) with x:

          8 / 2x = 4 / x = 4 / (2+2) = 1

          Implicit multiplication takes priority over division.

          My Casio fx-991 gives 1. If I put in an explicit multiplication, then I get 16.