GPA and significant digits

[drb]

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Because of the averaging over several dozen courses, the “GPA variance” will be about an order of magnitude smaller than the “individual course-grade variance”, and in that sense, the GPA is accurate to an extra digit or so beyond the accuracy of the individual course grades.

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<p>Is this true? I would imagine if grades were assigned as, for example, 3.3 +/- 0.1, the average value (i.e. the GPA) would have to be reported as a confidence interval, and not given a 3 digit definite value.</p>

<p>And I do not think you can substitute the latter for the former because it “feels right”.</p>