What percent of the observations in a distribution lie between the first quartile and the third quartile?
A. 75%.
B. 50%.
C. 25%.
D. None of the above.
50%
75%
First quartile = 25%
Third quartile = 75%
75%
To determine what percent of the observations in a distribution lie between the first quartile (Q1) and the third quartile (Q3), you need to understand the concept of quartiles.
Quartiles divide a dataset into four equal groups. The first quartile (Q1) represents the 25th percentile, which means 25% of the data falls below this value. The third quartile (Q3) represents the 75th percentile, indicating that 75% of the data falls below this value.
Since the first quartile represents the 25th percentile and the third quartile represents the 75th percentile, the observations between Q1 and Q3 represent the middle 50% of the data. This is because the difference between Q3 and Q1 covers the interquartile range (IQR), which contains the central half of the dataset.
Therefore, the answer to the question is B. 50% of the observations lie between the first quartile and the third quartile.