1. Introduction: the value that shows up the most
Think about a small shoe shop in your neighbourhood. All day, people come and buy shoes. The shopkeeper does not really care about the "average" shoe size. What she wants to know is: which size sells the most? That is the size she must keep stacked near the door.
That "most common" value has a name in mathematics. It is called the mode.
Here is the idea in one line. The mode is the value that occurs most often in a set of data.
You already know two other ways to describe a bunch of numbers with a single number. You met the mean — the average, add-them-all-and-share-equally. You met the median — the middle value when data is lined up in order. The mode is the third member of this family. Each one answers a slightly different question:
- Mean asks: "If we shared everything equally, how much each?"
- Median asks: "What is the value right in the middle?"
- Mode asks: "What is the most typical, most-repeated value?"
In this lesson you will learn to find the mode — first for a plain list of numbers, then for grouped data, where numbers are bundled into class intervals like 0–10, 10–20, and so on.
Stop scrolling. In your own words, what does "mode" mean? Say it out loud before reading on.
By the end of this section you can now say what the mode measures and how it is different from the mean and the median.