A store owner wants to know the average sales for each day of the week.

The term “average” in this context refers to the mean, which is the most common measure of central tendency for numerical data. To calculate the mean daily sales, the store owner would add the sales values for the days being studied and divide by the number of days. This provides a single summary value representing the typical sales amount across the week. Variance measures how much the daily sales differ from one another, not the average itself. Distribution describes the overall pattern of the data, such as whether sales are clustered, spread out, or skewed. Median identifies the middle value when observations are ordered from smallest to largest, which can be useful when data are highly skewed, but it is not the standard interpretation of “average” unless specifically stated. Because the question asks directly for the average sales for each day of the week, the most accurate statistical measure is the mean. Thus, the correct answer is mean, which summarizes daily sales using arithmetic average.