In math, the mean is a type of average that is calculated by adding all the numbers in a data set and then dividing the sum by the number of numbers in the set. It is a measure of central tendency that represents the typical value of a set of numbers. The mean is also known as the arithmetic mean, and it is often used in statistics to summarize data. To calculate the mean, you add up all the numbers in the set and then divide by the total number of numbers. For example, the mean of the numbers 6, 11, and 7 is (6+11+7)/3 = 8. The mean can be used to improve fluency skills of addition and encourage students to use mental math methods to do these additions. It is also used in real-life situations, such as by the United States Census Bureau to find the average age of the population.