Using statistical concepts, it is found that:
- The mean practice time decreases because of the outlier.
- The median practice time does not change because of the outlier.
- The range increases because of the oulier.
What are the mean, the median and the range of a data-set?
- The mean is the sum of all observations divided by the number of observations.
- The median is the middle value, the value that separates the upper 50% from the bottom 50%.
- The range is the difference between the largest value and the smallest.
From their concepts above, we have that the mean and the range are influenced by outliers.
In this problem, the outlier is at the low end, of 15, hence:
- The mean practice time decreases because of the outlier.
- The median practice time does not change because of the outlier.
- The range increases because of the oulier.
More can be learned about statistical concepts at https://brainly.com/question/24732674
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