The 75th percentile is referred to as the
a. first quartile
b. second quartile
c. third quartile
d. fourth quartile
The correct answer and explanation is :
The correct answer is c. third quartile.
Explanation:
In statistics, quartiles are values that divide a data set into four equal parts, with each part containing 25% of the data. These quartiles help summarize the distribution of data and are often used to understand the spread and center of a data set.
- First quartile (Q1): This is the 25th percentile. It is the value below which 25% of the data fall. It divides the lower quarter of the data from the rest.
- Second quartile (Q2): This is the 50th percentile, also known as the median. It divides the data set into two equal halves. Half of the data lies below this point, and half lies above it.
- Third quartile (Q3): This is the 75th percentile. It is the value below which 75% of the data fall. It marks the boundary between the lower 75% and the upper 25% of the data.
- Fourth quartile: This term does not technically exist in statistical terminology. The data above the third quartile (Q3) represents the upper 25% of the data, but there is no specific “fourth quartile.”
In the context of a data set, if you were to split the data into four quarters, the 75th percentile is the point at which three-quarters of the data have values less than or equal to it, and the remaining one-quarter of the data lies above it. The third quartile is important for understanding the upper distribution of the data.
For example, in a set of test scores, the third quartile would represent the score below which 75% of the students scored. It provides a way to measure the spread and helps identify whether most values are concentrated in the lower or upper ranges of the data.