Mathematics for IGCSE & O level - Statistical Diagrams (Section 5 - No. 33)
In a cumulative frequency diagram, the upper quartile can be found by...
reading off the value corresponding to 25% of the total frequency.
reading off the value corresponding to 50% of the total frequency.
reading off the value corresponding to 75% of the total frequency.
reading off the value corresponding to 90% of the total frequency.
Explanation
The upper quartile is the 75th percentile.