Which property is shared by both the mean and the median?

• A. Uniqueness
• B. Not affected by extreme values
• C. Simplicity
• D. A measure of dispersion

Answer: (A)

Both the mean and the median reduce a data set to a single number that represents where the data are centered. The mean is a unique value computed from all data points, and the median is defined as the middle value when the data are ordered (for an even number of observations, the median is the average of the two middle values), which also gives a single, definite number. Because both provide one central location for the data, they share this property. The mean, however, is sensitive to extreme values, so not affected by extreme values isn’t a shared trait. They describe location, not dispersion, and while both can be computed with relative ease, the key shared idea is that each yields one central value for the dataset.