GPA and significant digits

[siserune]

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@drb

Letter grade equivalents are usually reported as two significant digits (e.g., 3.3 or 4.0) but GPAs are often reported to three significant digits (e.g. 3.45). Isn’t this incorrect (unless one considers the equivalent an exact number, but this doesn’t seem right)? Shouldn’t the 3.45 be rounded to 3.5?

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<p>No. In terms of “significant figures”, the extra digit of accuracy in the GPA is correct.
Knowing the numeric course grades to an accuracy of 0.1 apiece does in fact correspond to about 5-10 times greater accuracy
(hence an extra significant digit) in the knowledge of the GPA. This is because the grades are averaged over several dozen courses.</p>