1-8 Boxplots
Boxplots divide the data into four quartiles
25%
Min
25%
Q1
25%
25%
Q2
Q3
Max
Example 1: Listed below you will find the cost (in dollars) of 11 different types of graphing calculators.
60 62 63 68 69 71 75 79 80 88 110
Five Number Summary:
Min:
Q1:
Q2:
Q3:
Max:
FINDING OUTLIERS
1. Compute the Interquartile Range (IQR) = Q3-Q1
2. A number is an outlier if it is 1.5(IQR) greater than Q3 or 1.5(IQR) less than Q1
Q3 + IQR(1.5)
Q1- IQR(1.5)
Graph Boxplot ( be sure to label the axes)
Example 2: Listed below you will find the number of calories in ten different types of ice cream bars.
75 135 151 151 182 183 190 200 200 200
Five Number Summary
Min =
Q1=
Median=
Check for outliers :
Graph Boxplot (be sure to label the axes)
Q3=
Max=
1-8 Boxplots