Mean, Median and Mode
Three ways to find the center of a data set.
About this topic
Mean, median and mode are measures of centre. The mean is the sum divided by the count, the median is the middle value when sorted (or the average of the two middle values), and the mode is the most frequent value.
The mean uses every value but is pulled by outliers, so for skewed data such as house prices or salaries the median often describes a typical case better. The mode is the only measure that works for categories, like the most popular shoe size or favourite colour. A data set can have no mode, one mode or several.
Example: for the scores 4, 6, 6, 7, 12 the mean is 35/5 = 7, the median is 6 and the mode is 6. If an extreme score of 100 replaces the 12, the mean jumps to 24.6 while the median stays at 6, which shows how robust the median is.
These measures summarise everything from test grades to incomes and sports statistics. Tips: sort the data before finding the median, check by counting that you have the right number of values, and say which measure you are using, since saying average alone can be misleading and is sometimes used deliberately to mislead.
Key ideas
- Mean is the average
- Median is the middle value when sorted
- Mode is the most frequent
Quick check
Use cases: where Mean, Median and Mode helps
- Homework: review the key idea behind Mean, Median and Mode before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Mean, Median and Mode without notes.
- Visual learning: play with the interactive lab to see how Mean, Median and Mode changes when you adjust its inputs.
- Teaching a friend: explain Mean, Median and Mode in your own words, then compare your version with the key ideas.
Number and algebra skills are used in science, engineering, budgeting and computing.
Frequently asked questions
What is Mean, Median and Mode?
Three ways to find the center of a data set.
What will I learn in Mean, Median and Mode?
Mean is the average. Median is the middle value when sorted. Mode is the most frequent.
Is Mean, Median and Mode part of Mathematics?
Yes. It is one of 200 Mathematics topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Mean, Median and Mode lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Mean, Median and Mode?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.