• Blackmist@feddit.uk
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    7 天前

    We had computer classes where we had to learn about spreadsheets.

    To do a number plus ten percent we had to put in A1+A1*10/100

    I did A1*1.1 like a normal person.

    She then went round to make sure everyone had put it in correctly. Got annoyed at me and changed A1 to something else to expose my folly.

    Was visibly annoyed when it showed the right answer.

    • needanke@feddit.org
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      7 天前

      (I don’t think that was your teachers point at all, but) couldn’t the different formulas have produced different rounding errors due to floating point percision?

        • gandalf_der_12te@discuss.tchncs.de
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          7 天前

          yeah because excel does rounding stuff automatically for you

          try entering 0.1 + 0.2 - 0.1 - 0.2 == 0.0 in any programming language of your choice and see what happens.

      • Blackmist@feddit.uk
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        7 天前

        Doubtful, but if anything mine would be more accurate. Fewer calculation steps to lose precision on. I think most spreadsheet software fudges floating point precision anyway. A computer programmer may accept that 0.1+0.2 is not 0.3 but an accountant or mathematician would not be having it.

        I think she was just shit at maths tbh. As a kid you sort of assume all the teachers know more than you about every subject, and that’s not the case at all.