The 25th percentile is another name for the lower quartile (Q1).
To understand why, let's break it down step-by-step:
1. Percentiles Explained:
Percentiles are used in statistics to divide a data set into 100 equal parts. For example, the 25th percentile is the value below which 25% of the data fall.
2. Quartiles:
Quartiles divide data into four equal parts:
- The first quartile (Q1) or the lower quartile is the 25th percentile.
- The second quartile (Q2) is the median or the 50th percentile.
- The third quartile (Q3) or the upper quartile is the 75th percentile.
3. Finding the Specific Quartile:
Based on the definitions:
- The lower quartile (Q1) is the value that cuts off the first 25% of the data when it is sorted in ascending order.
- The median (Q2) cuts the data into two equal halves at the 50th percentile.
- The upper quartile (Q3) is the value that cuts off the first 75% of the data.
Given this information, we understand that the term "25th percentile" directly corresponds to the "lower quartile."
Therefore, the answer to the question is the lower quartile.
