What is the first step to calculate the mean of a data set?

To calculate the mean of a data set, the initial action to take is to add all the values together. This step is essential because the mean is defined as the sum of all the values in the data set divided by the number of values. Once you have the total sum, you can easily determine the mean by dividing that total by how many values there are.

Ordering the values, finding the median, or determining the mode—while useful for other types of analyses—are not foundational steps in calculating the mean. They pertain to different measures of central tendency or specific data organization but do not directly contribute to arriving at the mean itself. Therefore, summing the values is the first and crucial step in the process of finding the mean.