Final answer:
To find the IQR on a box plot, subtract the first quartile (Q1) from the third quartile (Q3).
Step-by-step explanation:
To find the interquartile range (IQR) on a box plot, you need to calculate the difference between the third quartile (Q3) and the first quartile (Q1). The IQR represents the spread of the middle 50 percent of the data. Here is the formula:
IQR = Q3 - Q1
For example, if the Q3 value is 9 and the Q1 value is 2, the IQR would be 9 - 2 = 7.