Interquartile Range is the spread between which percentiles?

Interquartile Range is the spread between which percentiles?

• A. 25th and 75th centiles
• B. 0th and 100th centiles
• C. 50th and 100th centiles
• D. 10th and 90th centiles

Answer: (A)

The interquartile range reflects the spread of the middle half of the data. It is the difference between the third quartile (75th percentile) and the first quartile (25th percentile). In other words, it measures how wide the central 50% of observations are. Because it relies on quartiles, it is less influenced by outliers than the full range, which spans from the 0th to the 100th percentile. So, the spread between the 25th and 75th centiles captures the IQR. For example, if Q1 is 20 and Q3 is 60, the IQR is 40.

The interquartile range reflects the spread of the middle half of the data. It is the difference between the third quartile (75th percentile) and the first quartile (25th percentile). In other words, it measures how wide the central 50% of observations are. Because it relies on quartiles, it is less influenced by outliers than the full range, which spans from the 0th to the 100th percentile. So, the spread between the 25th and 75th centiles captures the IQR. For example, if Q1 is 20 and Q3 is 60, the IQR is 40.