Answer
The mean is -14.25, mode: -32, the median is -12, the mid range is -10.5.
Work Step by Step
The mean can be counted by summing all the data and dividing it by the number of data: $\frac{-15-18-32-21-9-32+11+2}{8}=-14.25$, the mean is -14.25. The mode is the data occurring the most times, which here is -32 appearing twice. The median is the average of the 1 or 2 (here 2) middle data: (-15-9)/2=-12, the median is -12. The mid range is the average of the highest and the lowest data: (-32+11)/2=-10.5, the mid range is -10.5. American Airlines' performance is rally good because most of their flights seem to arrive early.