IQR = Q3 - Q1 Upper fence value = Q3 + (1.5×IQR) Lower fence value = Q1 - (1.5×IQR)
Work Step by Step
a. )Rearrange the values in ascending order: 13,13,14,14,15,15,16,20,21,26 The Median or Q3: (15 + 15)/2 = 15 Median of Lower Half Observations: 14 Median of Upper Half Observations: 20 b.) IQR = Q3 - Q1 IQR = 20 - 14 = 6 c.) Upper fence value = Q3 + (1.5×IQR) = 20 + (1.5×6) = 29 An observation would have to be greater than 29 to be an outlier.