Is it possible to have a quiz question be worth a percentage instead of a point value?
If you make the quiz worth 100 points, then the points are the percentage. That's probably not what you wanted, but I thought I'd mention it.
Otherwise, this cannot be done with the existing (legacy) version of Quizzes. However, there was a feature request for this: Show quiz as percent score in Gradebook. . It was marked as completed by Canvas because Quizzes.Next supports it. They are not doing any additional development on the legacy version of the quizzes, so it is unlikely that this will happen for the legacy quizzes.
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