Answer:
IQR = 13
Step-by-step explanation:
first step is to find the median of the data set.
rearrange the data into ascending order. Then the median is the middle value.
1 , 6 , 7 , 8 , 12 , 19 , 30 ← in ascending order
↑ middle
then median = 8
the interquartile range (IQR) is calculated as
IQR = Q₃ - Q₁ ( Q₃ is the upper quartile and Q₁ the lower quartile )
Q₃ is the middle value of the data to the right of the median
12 , 19 , 30
↑ middle
then Q₃ = 19
Q₁ is the middle value of the data to the left of the median
1 , 6 , 7
↑ middle
then Q₃ = 6
IQR = 19 - 6 = 13
