GRAPHS AND STATISTICS

Median

Learn the reliable method for median, then apply it to 11+ exam-style questions.

1 · WHAT YOU NEED TO KNOW

The idea

The median is the middle value after the data have been ordered.

Picture itOrder values and find the middle
2 · THE METHOD

Follow these steps

  1. Put the values in numerical order.
  2. Find the central position.
  3. For an even number of values, find the mean of the two central values.
3 · WORKED EXAMPLES

See the method in action

Example 1

What is the median of 27, 36, 24, 31, 20?

  1. Order the values: 20, 24, 27, 31, 36.
  2. The third of five values is 27.
Answer: 27
Example 2

The data are 25, 30, 21, 14, 18. A value of 33 is added. What is the new median?

  1. Order all six values: 14, 18, 21, 25, 30, 33.
  2. Average the third and fourth to get 23.
Answer: 23
4 · ELEVENSPRINT TIP

A useful shortcut

For an even number of values, find the mean of the two central values.

5 · COMMON MISTAKES

Watch out for these

6 · TRY IT YOURSELF

Three fresh questions

Ready to check the method? You will get three fresh, validated questions.