BUILD FLUENCY. EARN YOUR ASCENT.Sign in Year 10
Quartiles, IQR and the middle half
Free examples and worked answers. No account needed.
Practise the method.
Quartiles, IQR and the middle half
Quartiles, IQR and the middle half
Example 1
What is the interquartile range (IQR)?
Show worked answer
Answer: 20
- IQR=Q3−Q1=40−20=20.
Example 2
What percentage of observations lies between Q1 and Q3?
Show worked answer
Answer: 50
- The box spans the middle half of the data, or 50%.
Example 3
Approximately what percentage of observations is at or below Q3?
Show worked answer
Answer: 75
- Q3 is the 75th percentile.
- With tied values the actual percentage can be higher
- this is the usual quartile interpretation.
Put it into practice.
Sign in to choose a set, get feedback and keep your progress.