To analyze the average test scores, we first calculate the frequency of each score. The average test scores are:
\[
\{82, 81, 79, 79, 78, 80, 77, 78, 80, 76\}
\]
The frequency distribution is as follows:
- \(82\) appears \(1\) time
- \(81\) appears \(1\) time
- \(79\) appears \(2\) times
- \(78\) appears \(2\) times
- \(80\) appears \(2\) times
- \(77\) appears \(1\) time
- \(76\) appears \(1\) time
Next, we calculate the relative frequency for each score by dividing the frequency of each score by the total number of scores, which is \(10\):
\[
\text{Relative Frequency} = \frac{\text{Frequency}}{\text{Total Scores}}
\]
The relative frequency distribution is:
\[
\begin{align_}
82 & : \frac{1}{10} = 0.1 \\
81 & : \frac{1}{10} = 0.1 \\
79 & : \frac{2}{10} = 0.2 \\
78 & : \frac{2}{10} = 0.2 \\
80 & : \frac{2}{10} = 0.2 \\
77 & : \frac{1}{10} = 0.1 \\
76 & : \frac{1}{10} = 0.1 \\
\end{align_}
\]
To find the relative frequency of scores that are at least \(80\), we sum the relative frequencies of the scores \(80\) and \(82\):
\[
\text{Relative Frequency of scores} \geq 80 = P(80) + P(82)
\]
Substituting the values:
\[
= 0.2 + 0.1 = 0.3
\]
Thus, the relative frequency of average test scores of at least \(80\) is \(0.3\).