What do you mean by "explain the 2 extremes occuring at the same time?"?

Is there anything to explain? Recompute the statistics with each of them removed, and with both of them removed.

Depends on the origin or the outliers, if they are legitimate data from the tails of the sampling distribution then that is one thing, if they are due to experimental error and are not legitimate samples then discard them.and the range will be larger so that it can not represent the data range correctly. Is this correct?

CB