given the following set of data:
124, 129, 132, 134, 144, 128, 131.
we were asked to use the interquartile range to identify any outliers.
firstly, let us arrange the given set of data in ascending order
124, 128, 129, 131, 132, 134, 144
so we can get our Interquartile Range
Interquartile Range (IQR) = Q3 - Q1
Q1 = 128
Q3 = 134
IQR = 134 - 128
IQR = 6
so let's get the outlier
lets multiply IQR by 1.5
= 6 x 1.5
= 9
subtract 9 from Q1
= 128 - 9 = 119
There is no Data less than 119
lets add 9 to Q3
= 134 + 9
= 143
144 is greater than 143
therefore, 144 is an Outlier
so the correct option is the last option which says that 144 is an Outlier.