Mean, Median, Mode — SAT Math Explained
Three measures of central tendency — statistical values that describe the 'center' or 'typical' value of a data set. Mean is the arithmetic average, median is the middle value, and mode is the most frequent value.
The Core Idea
No single measure is always best — each tells a different story about the data. The choice of which to use depends on the shape of the distribution and the presence of outliers.
Definitions
The sum of all values divided by the count of values — sensitive to outliers
The middle value when data is ordered — robust against outliers
The value(s) appearing most frequently — useful for categorical data
If all values appear equally often, there is no mode
Two values tied for most frequent
How To Calculate
Add all values, divide by n (count)
Sort data, take the middle value
Sort data, average the two middle values
Sort and count frequencies; the most frequent is the mode
When To Use Which
Best for symmetric distributions with no extreme outliers
Best when outliers are present or data is skewed (income, home prices)
Best for categorical data or finding most common value (shoe sizes, grades)
Effect Of Outliers
The mean is pulled toward outliers; the median is resistant. Example: if 5 people earn $30K and one earns $1M, the mean is misleading but the median accurately reflects the typical earner.
Common Errors to Avoid
Forgetting to sort data before finding the median
Finding the median position without averaging when n is even
Confusing mean and median when both are asked
Practice: Mean, Median, Mode
5 SAT-style questions. Select your answer and get an instant explanation.
What is the mean of the data set: 4, 8, 10, 12, 16?
Want More Mean, Median, Mode Practice?
Blitzsat's question bank has thousands of SAT-style questions across every topic in Problem Solving & Data Analysis. Filter by topic and difficulty. Get AI-powered questions generated from your own notes.
Practice & Explore: Mean, Median, Mode
Apply what you just learned — practice questions, full tests, and related study resources.