7.11. Box-and-Whisker Plots http://www.ck12.org
The first step is to organize the data values as follows:
20 ,400 21,300 22,200 25,000 26,900 28,700 28,800 34,300 54,700 65, 000
Now calculate the median,Q 1 , andQ 3.
20 ,400 21,300 22,200 25, 000 26 ,900 28, 700 28 ,800 34,300 54,700 65, 000
Median→26 , 900 + 28 , 700
2
=
55 , 600
2
= 27 , 800
Q 1 = 22 , 200
Q 3 = 34 , 300
Next, complete the following list:
Minimum value→ 20 , 400
Q 1 → 22 , 200
Median→ 27 , 800
Q 3 → 34 , 300
Maximum value→ 65 , 000
The right whisker is longer than the left whisker, which indicates that the distribution is positively skewed.
Example C
Using the procedure outlined above, check the following data sets for outliers:
a. 18, 20, 24, 21, 5, 23, 19, 22
b. 13, 15, 19, 14, 26, 17, 12, 42, 18
a. Organize the given data set as follows: