Key learning points

1. A cumulative frequency has values read in the same way as a line graph
2. The median is the 50th percentile
3. The lower quartile is the 25th percentile
4. The upper quartile is the 75th percentile
5. Other percentiles can also be found

Keywords

• Percentile - A percentile is a value on a scale of 100 that indicates the percent of a distribution that is equal to or below it.

• Lower quartile - The lower quartile is the value under which 25% of data points are found when they are arranged in increasing order. Also known as the first quartile (Q1).

• Upper quartile - The upper quartile is the value under which 75% of data points are found when they are arranged in increasing order. Also known as the third quartile (Q3).

Common misconception