Question

1. the box plots below describe the test scores on a recent math test in two classes. what is the interquartile range (iqr) of the test scores for each class? make a comparative inference about the populations based on the iqr. class 1 class 2 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 test score test score class 1 iqr is 40 and class 2 iqr is 35 sc-3 make comparative inferences about populations sc3-7

Explanation:

Step1: Recall IQR formula

The inter - quartile range (IQR) is calculated as $IQR = Q_3 - Q_1$, where $Q_3$ is the third - quartile and $Q_1$ is the first - quartile. In a box - plot, the left edge of the box is $Q_1$ and the right edge of the box is $Q_3$.

Step2: Calculate Class 1 IQR

For Class 1, assume $Q_1 = 30$ and $Q_3 = 70$. Then $IQR_1=70 - 30=40$.

Step3: Calculate Class 2 IQR

For Class 2, assume $Q_1 = 40$ and $Q_3 = 75$. Then $IQR_2 = 75 - 40=35$.

Step4: Make comparative inference

A larger IQR (Class 1 with IQR = 40) indicates that the middle 50% of the test scores in Class 1 are more spread out than the middle 50% of the test scores in Class 2 (with IQR = 35). So, the scores of students in Class 1 are more variable in the middle 50% of the data compared to Class 2.

Answer:

The IQR of Class 1 is 40 and the IQR of Class 2 is 35. The middle 50% of the test - scores in Class 1 are more spread out than the middle 50% of the test - scores in Class 2.