# Box and Whisker Plots A K A Box

Box and Whisker Plots A. K. A Box Plots

What makes up a box plot? #4 Lower/First Quartile #2 Lower Extreme #5 Upper/Third Quartile #1 Median #3 Upper Extreme BELOW a number line ABOVE or _____ The box plot is placed either _____ NOT on the number line ______

#1: Median The ______ value when the data is _______ #2: Lower/First Quartile The ______ value of the _____ half of the data #3: Upper/Third Quartile The ______ value of the _____ half of the data

#4: Lower Extreme The ______ value #5: Upper Extreme The ______ value #6: Interquartile Range The _________ between the _____ and ______ quartiles.

Example #1

24, 20, 18, 25, 22, 30, 29, 35, 30, 28, 24, 38 1 st - put the data in order 2 nd - find the median 3 rd - find the LQ 4 th - find the UQ 5 th - find the Lower Extreme 6 th - find the Upper Extreme 18 20 22 24 24 25 28 29 30 30 32 35 38 23 Lower _____ Extreme 31 Upper _____ Lower _____ Upper _____Extreme Quartile Median _____ Quartile

Lower _____ Upper _____ Extreme Lower _____ Upper _____Extreme Quartile Median _____ Quartile • 18 • 20 22 • 24 26 28 • 30 • 32 34 36 Interquartile Range: upper quartile lower quartile 31 - 23 = 8 38 40 42 44

18 20 22 24 24 25 28 29 30 30 32 35 38 LQ Median UQ What percent of the data falls between the Lower Extreme and the Lower Quartile? 25% - a quarter What percent of the data falls between the Lower Quartile and the Median? 25% - a quarter What percent of the data falls between the Median and the Upper Quartile? 25% - a quarter What percent of the data falls between The Upper Quartile and the Upper Extreme? 25% - a quarter

Example #2

32, 12, 38, 42, 54, 26, 18, 30, 50, 44 1 st - put the data in order 2 nd - find the median 3 rd - find the LQ 12 18 26 30 32 26 Lower _____ Extreme 4 th - find the UQ 5 th - find the Lower Extreme 6 th - find the Upper Extreme 35 38 42 44 50 54 44 Upper _____ Lower _____ Upper _____Extreme Quartile Median _____ Quartile

Lower _____ Upper _____ Extreme Lower _____ Upper _____Extreme Quartile Median _____ Quartile • 12 • 16 20 24 • 28 32 36 • 40 44 • 48 Interquartile Range: upper quartile lower quartile 44 - 26 = 18 52 56 60 64

Finding Information From a Box Plot

5 1. What is the median? _______ 7 2. What is the upper quartile? _______ Cannot be determined 3. How many people were surveyed? _______ 7 -3=4 4. What is the IQR? ____ -2= 5. What is the range of the data? 8 ______ 6 Cannot be determined 6. What is the mean? _____

12 1. What is the lower quartile? _______ 21 2. What is the upper quartile? _______ - 8 = 14 3. What is the range of the data? 22 _______ 21 - 12 4. What is the IQR? ____ =9 25% 5. What percent of the data falls between 8 and 12? ______ 50% 6. What percent of the data is more than 15? _____

Use the data in the table to create a box plot.

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