Answer:
IQR= .85
Explanation:
Interquartile range is used to find the middle %50 in a set.
When calculating inner quartile range you should begin by arranging the points from least to greatest.
30.8, 29.9, 30.0, 31.0, 30.1, 30.5, 30.7, 31.0
↓
29.9, 30.0, 30.1, 30.5, 30.7, 30.8, 31.0, 31.0
Calculate the median of the set. Since we have an even number of items in the set, we will calculate this by finding the average of the two center items.
30.5+30.7= 61.2 61.2/ 2= 30.6
Using the two centermost values(same values used above) separate the set into an upper(right) and a lower(left) half.
29.9, 30.0, 30.1, 30.5║ 30.7, 30.8, 31.0, 31.0
Find the median of both of the sets by averaging the center values.
(upper) 30.7, 30.8, 31.0, 31.0 30.8+ 31.0= 61.8/ 2= 30.9
(lower) 29.9, 30.0, 30.1, 30.5 30.0+30.1= 60.1/ 2= 30.05
Last we need to calculate the difference in the upper median and lower median. The inner quartile range is equal to this difference.
30.9- 30.05= IQR= .85