The document discusses various measures of central tendency including the arithmetic mean, median, mode, geometric mean, and harmonic mean. It provides formulas and examples for calculating the arithmetic mean and median. Specifically, it defines the arithmetic mean as the sum of all values divided by the total number of values. An example is shown of calculating the mean for a set of test scores by placing them in a frequency distribution table and using the formula Σfx/Σf. The median is defined as the middle value when values are arranged in order, or the average of the two middle values for an even distribution. A formula is given for finding the median of grouped data using cumulative frequencies.