Answer
The mean will decrease
Step-by-step explanation
An outlier is an observation that lies an abnormal distance from other values in a dataset. In the case of the dataset:
4, 5, 5, 6, 7, 8, 17
the outlier is 17
The mean is calculated as follows:
[tex]mean=\frac{sum\text{ of terms}}{number\text{ of terms}}[/tex]Then, the mean of the original dataset is:
[tex]\begin{gathered} mean=\frac{4+5+5+6+7+8+17}{7} \\ mean=\frac{52}{7} \\ mean\approx7.4 \end{gathered}[/tex]After 17 is removed from the set, the mean is:
[tex]\begin{gathered} mean=\frac{4+5+5+6+7+8}{6} \\ mean=\frac{35}{6} \\ mean\approx5.8 \end{gathered}[/tex]The mean will decrease if the outlier is removed