IB skill practice

Interpret box plots and cumulative frequency

Interpret quartiles, interquartile range, outlier boundaries, and distribution summaries.

Paper 1 5 marks Difficulty 2

Find quartiles and interquartile range

The ordered data set is \(14, 16, 18, 20, 25, 27, 31, 34, 36\). Find \(Q_1\), \(Q_3\), the interquartile range, and the upper outlier boundary.

Worked practice: quartiles and outliers

Read the quartiles, find the interquartile range, then calculate the upper outlier boundary.