1. Pay attention to the table below.
$\displaystyle \begin{array}{|c|c|c|c|c|c|}\hline Frequency & 5 & 6 & 7 & 8 & 9 \\ \hline Score & 6 & 6 & 10 & 15 & 5\\ \hline \end{array}$
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 $\displaystyle \frac{291}{35}$, 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 $\displaystyle \frac{291}{42}$ 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?

2. 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:

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

It would appear 20 students scored higher than the mean.