# Average

The average is a single number used to represent a set of numbers. Some common kinds of averages include: the arithmetic mean (usually called the mean), the median, and the mode.

### mean

The mean, also referred to as the arithmetic mean, is likely the most familiar kind of average.

Example

Cheryl earned the following points on math tests:

88, 88, 43, 96, 85

To find the mean, find the total points scored:

88 + 88 + 43 + 96 + 85 = 400

Then divide the total points by the number of tests taken.

400 ÷ 5 = 80

### median

The median is the middle number for a set of data when the data are ordered from least to greatest or greatest to least.

Example

To find the median of Cheryl's scores, arrange the points in numerical order: 43, 85, 88, 88, 96. The median is the middle number, 88.

### mode

The mode for a set of numbers is the number or numbers that occur most often.

Example

The mode for Cheryl's test scores is 88 because it occurs twice, and each of the other scores occurs only once.

### Did you know?

The average length lifespan in the United States is nearly 80 years.