Q. Select the outlier in the data set. 20,27,33,39,51,60,76,94,685
Arrange Data Set: Arrange the data set in ascending order.The data set is already in ascending order: 20,27,33,39,51,60,76,94,685.
Calculate IQR: Calculate the interquartile range (IQR) of the data set.First, find the medianQ2, which is the middle value when the data is ordered. For our data set, the median is 51.Next, find Q1, the median of the lower half of the data set (not including Q2). The lower half is 20,27,33,39, so Q1 is the average of 27 and 33, which is 227+33=30.Then, find Q3, the median of the upper half of the data set (not including Q2). The upper half is 511, so Q3 is the average of 513 and 514, which is 515.Now, calculate the IQR: 516.
Determine Outlier Boundaries: Determine the outlier boundaries.The lower boundary for outliers is Q1−1.5×IQR=30−1.5×55=30−82.5=−52.5 (since there can't be negative values in this context, we'll consider the lower boundary as the smallest value in the data set, which is 20).The upper boundary for outliers is Q3+1.5×IQR=85+1.5×55=85+82.5=167.5.
Identify Outliers: Identify any values outside the outlier boundaries.Looking at the data set, the value 685 is clearly above the upper boundary of 167.5, so it is an outlier.
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