Post on 29-Dec-2015
Lesson 12-3 Pages 617-621
Box-and-Whisker Plots
1.Display data in a box-and-whisker plot.
2.Interpret data in a box-and-whisker plot.
What you will learn!1. How to display data in a box-and-whisker plot.
2. How to interpret data in a box-and-whisker plot.
Box-and-whisker Box-and-whisker plotplot
What you really need to know!
A box-and-whisker plot divides a set of data into four parts using the median and quartiles. Each of these parts contain 25% of the data.
What you really need to know!
Lower Extreme
Lower Quartile
Upper Extreme
Upper Quartile
Median
Example 1:The projected number of employees in 2008 in the fastest growing occupation is shown in the table below. Display the data in a box and whisker plot.
Fastest-Growing JobsFastest-Growing Jobs
OccupationOccupation Jobs Jobs (1000s(1000s
))
OccupationOccupation Jobs Jobs (1000s)(1000s)
Computer Computer EngineerEngineer
622622 Desktop Desktop PublishingPublishing
4444
Computer Computer SupportSupport
869869 Paralegal/Legal Paralegal/Legal AssistantAssistant
220220
Systems Systems AnalystAnalyst
11941194 Home Health Home Health AideAide
11791179
Database Database AdministratorAdministrator
155155 Medical Medical AssistantAssistant
398398
4444 155155 220220 398398 622622 869869 11711799
11911944
Lower half of data Upper half of dataLQ is 187.5
Median between 398 and 622.
398 + 622 = 1,020
1,020 ÷ 2 = 510
UQ is 1,024
00 200200 400400 600600 800800 10010000
12012000
14014000
16016000
44
187.5
1,194
1,024
510
2020 3030 4040 5050 6060 7070 8080 9090 1010
00
Example 2:
The box-and-whisker plot below shows the average percent of sunny days per year for selected cities in each state.
2020 3030 4040 5050 6060 7070 8080 9090 1010
00
Example 2:
What is the smallest percent of sunny days in any state?
23%
2020 3030 4040 5050 6060 7070 8080 9090 1010
00
Example 2:
Half of the selected cities have an average of sunny days under what percent? 56%
2020 3030 4040 5050 6060 7070 8080 9090 1010
00
Example 2:
What does the length of the box in the plot tell us about the data?
Since the box is short, the data is clustered together!
00 2525 5050 7575 100100
Example 3:
Evergreen Trees
Deciduous Trees
The average maximum height, in feet, for selected evergreen and deciduous tress is displayed. How do the heights of evergreen tress compare with the heights of deciduous trees?
Most evergreen trees are taller than most deciduous trees.
Page 619-620
Guided Practice
#’s 4-9
Pages 617-619 with someone at home and
study examples!
Read:
Homework: Pages 620-621
#’s 10, 12, 14, 16, 17
#’s 22, 23, 26-29
Lesson Check 12-3
Page
753
Lesson 12-3