The lower quartile, also known as the first quartile, is a number that helps to divide a set of data into four equal parts. When you put all the numbers in a data set in order from smallest to largest, the lower quartile is the value that lies one-quarter (or 25%) of the way through the list. This means that roughly 25% of the numbers are less than or equal to the lower quartile (and roughly 75% of the numbers are greater than or equal to it).
Finding the lower quartile is a useful way to understand the spread and distribution of data, especially when comparing different groups of information. It gives you an idea of the lower end or bottom quarter of the data.
Examiner-written GCSE Maths revision resources that improve your grades 2x
- Written by expert teachers and examiners
- Aligned to exam specifications
- Everything you need to know, and nothing you don’t
Share this article
written revision resources that improve your