.Answer:
D. 12.3
Step-by-step explanation:
Arrange the data in increasing order
3.4, 10.8, 16.7, 23.1, 31.5
⇒This is an odd set of numbers, to find the interquartile range you include the median in both quartiles.
Locate the median/center value
3.4, 10.8, 16.7, 23.1, 31.5
Find lower half and find the median
lower half values⇒3.4, 10.8, 16.7
Median=Q1=10.8
Find the upper half and find
upper half= 16.7,23.1, 31.5
median= 16.7,23.1,31.5
Q3=23.1
Interquartile range=Q3-Q1
23.1-10.8=12.3