we have the data set
75,69,82,90,75,73,108,79,80
step 1
order from least to greater
69 73 75 75 79 80 82 90 108
Min=69
Max=108
Median=79
Q1=(73+75)/2=74
Q3=(82+90)/2=86
To find out the outliers
step 1
Find IQR -------> interquartile range
IQR=Q3-Q1
we have
Q3=86
Q1=74
IQR=86-74=12
Find out 1.5IQR -----> 1.5 times the interquartile range
1.5*(12)=18
so
Our fences will be 18 points below Q1 and 18 points above Q3
Lower fence=74-18=53
Upper fence=86+18=104
Any scores that are less than 53 and greater than 104 are outliers
In this case
108 is the outlier