QuestionA professor has recorded exam grades for 10 students in his clas $s$, but one of the grades is no longer readable. If the mean score on the was 82 and the mean of the 9 readable scores is 84 , what is the value of the unreadable score?
The value of the unreadable score is $\square$

Studdy Solution
Determine the unreadable score by subtracting the sum of the 9 readable scores from the total sum of all 10 scores.
Let $x$ be the unreadable score. $$S_{10} = S_{9} + x$$ $$820 = 756 + x$$ $$x = 820 - 756$$ $$x = 64$$
The value of the unreadable score is $\boxed{64}$.