What does a box plot median of 12 represent?

• A. The smallest value
• B. The spread of the data
• C. The middle value of the data
• D. The average of the smallest and largest values

Answer: (C)

The median in a box plot is the middle value of the data when it’s arranged from smallest to largest. If the line inside the box sits at 12, that means half of the data are at or below 12 and half are at or above 12. It shows the center of the data, not the smallest value or the overall spread (which is shown by the box’s length and the whiskers). The average of the smallest and largest values is called the midrange, which is a different measure than the median. In datasets with an even number of points, the median is the average of the two middle values, and the box plot still reflects that central value.