GPA significa realmente calificación promedio:

In some countries, all grades from all current classes are averaged to create a grade point average (GPA) for the marking period.
http://en.wikipedia.org/wiki/GPA

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Pero aquí significa número de créditos computables:

http://www.georgian.edu/registrar/gpa.htm

To calculate your GPA, you need two numbers: your Quality Points and your GPA credits earned.
If you are a GCU student, you can easily get these two numbers from your online transcript. Just look for them on the last line of the transcript on the line marked "Cumulative" or "Cum". To calculate your GPA from these two numbers, you simply divide the total Quality Points by the total GPA Credits.

GPA =

Quality Points

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GPA Credits



http://www.edgewood.edu/GPA-Calculator

Your GPA represents the quotient of your quality points and your credit hours. The quality points you earn each term are calculated by multiplying the quantitative value of your grade times the credit hours for the course the grade represents...

The number of completed GPA credits are listed on the last line of the student transcript. This line lists the following: cumulative attempted credits, earned credits, and then GPA credits. GPA credits include all Edgewood College credits for which students received a letter grade (A-F).

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Note added at 2 horas (2014-04-29 09:15:25 GMT)
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Me he explicado un poco mal, no es que "signifique" computable, es que hace referencia a los módulos que se tienen en cuenta para calcular la calificación promedio.