Ontario Mathematics Proficiency Practice Test

The median is defined as the middle value in a data set when the numbers are arranged in ascending or descending order. To determine the median, you first need to sort the data points from smallest to largest. If there is an odd number of observations, the median is the value in the central position. If there is an even number of observations, the median is calculated by taking the average of the two middle values. This measure of central tendency is particularly useful because it is not affected by extreme values (outliers), making it a robust indicator of the data set's center.

In contrast, the sum of all values divided by the number of values represents the mean, not the median. The mode, which refers to the value that occurs most frequently in the data set, is another measure of central tendency but is distinct from the median. Similarly, identifying the largest value in the data set would give you the maximum, which is not related to the concept of median. Thus, the correct answer focuses specifically on the property of the median as the central point of a properly ordered set of numbers.