Answer:
Because of the presence of an outlier (30), an extremely higher value when compared to others. Outliers affects the value of mean, thereby mean should not be used for data with outliers.
Step-by-step explanation:
For the set of data above, it would be misleading to use the mean as the center of measure for the number of points that she scored in each game because of the presence of outliers, the presence of extremely lower or extremely higher value makes the use of mean as a measure of central tendency inaccurate because the mean take into consideration all the values in a data including the outliers for its calculation, and the mean would tend to shift towards the outliers thereby misinterpreting the data. The presence of outlier which is 30 in the data given would shift the mean to the right towards 30, thereby misleading to represent the measure of central tendency. 30 is an outlier because it is extremely higher than the rest of the data (10,8,9,8,30).
In the presence of outliers it's best to use median or mode as an acceptable measure of central tendency.
