Chapter 11 - Data Analysis and Displays - 11.1 - Measures of Center and Variation - Exercises - Page 590: 6

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$$12,9,17,15,10$$ Arrange in ascending order: $$9,10,12,15,17$$ The median is middle term $12$ There is no mode since none of the values occurs more often than others. The mean is: $$\frac{9+10+12+15+17}{5}=\frac{63}{5}=12.6$$ The median best describes the data because mean is more than most of the data values and there is no mode.