[ASK] Are the Frequency and the Score Switched?

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Monoxdifly
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Pay attention to the table below.
$$\begin{array}{|c|c|c|c|c|c|}\hline Frequency & 5 & 6 & 7 & 8 & 9 \\ \hline Score & 6 & 6 & 10 & 15 & 5\\ \hline \end{array}$$
The amount of students who get above average are...
A. 9 students
B. 17 students
C. 18 students
D. 26 students
I got the average as $$\frac{291}{35}$$, which is eight point something. So, I got 7 + 8 = 15 as the answer, but it was not in the option. I then assume that the frequency and score must be switched, but now I got $$\frac{291}{42}$$ which is six point something, so the answer should be 10 + 15 + 5 = 30 which was not in the options either. Where did I go wrong?
 
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Looking at the provided table, it appears the frequency and score are switched. Let's assume they are...

Using a weighted average, I get a mean score of:

$$\overline{x}=\frac{6\cdot5+6\cdot6+10\cdot7+15\cdot8+5\cdot9}{6+6+10+15+5}=\frac{301}{42}=\frac{43}{6}=7.1\overline{6}$$

It would appear 20 students scored higher than the mean. :D
 
That means, still no answer?