Here, we are required to determine how far the student described in the question is from the average.
The correct answer is Choice C: |x – 78|.
According to the question; the student received a score of x%.
As such, x% may either be greater or lesser than the average score, 78%.
Therefore, the expression that could be used to determine how far the student’s score is from the average is; |x – 78|
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