1. Warm – Up: Students will take a quiz,
January 23, 2013
Warm – Up: Students will take a quiz,
recalling information about mean, median, and average.
Click on the link below to begin:

2. January 23, 2013 Today you will take Cornell Notes on IQR. Please
Target: Given a set of data students
will be able to find the interquartile range
Don’t forget to copy the standard..
January 23, 2013
Today you will take Cornell Notes on IQR. Please
Follow the power point presentation carefully.
To become familiar with IQR please review the following 2 videos
Watch Me.
Watch Me.
Standard: MCC9-12.S.ID.2 Use statistics
Appropriate to the shape of the data distribution to compare center (median, mean)
And spread (interquartile range, standard deviation – Advanced Algebra) of two or more different
Data sets. Include review of Mean Absolute Deviation as a measure of variations
EQ: What does the interquartile range describe about a data set?

3. G Dear ©2010 – Not to be sold/Free to use
Stage 4
Year 9
Data Analysis
Note-Taking
Time!!!
Interquartile
Range
Press Ctrl-A
G Dear ©2010 – Not to be sold/Free to use

4. Interquartile Range (1/7)
(The Range of the middle 50% of scores)
IQR =
Q3 – Q1
What are Q3 and Q1?
Q1 is the lower quartile of 25th percentile.
Q3 is the upper quartile of 75th percentile.
Example 1
1, 3, 5, 6, 7, 8, 8
Median = 6
End of
Slide
Q3 = 8
Q1 = 3
IQR = Q3 - Q1
Middle of
top half.
Middle of
lower half.
= 8 - 3
= 5 4

5. Interquartile Range (2/7)
Example 2
2, 3, 6, 6, 7, 8.
Median = 6
Q3 = 7
Q1 = 3
IQR = Q3 - Q1
Middle of
top half.
Middle of
lower half.
= 7 - 3
= 4
Example 3
2, 3, 5, 6, 7, 9, 9, 10.
Median =
6.5
Q3 = 9
Q1 = 4
IQR = Q3 - Q1
Middle of
top half.
Middle of
lower half.
= 9 - 4
= 5
End of
Slide 5

6. Interquartile Range and Dot Plots (3/7)
Median Q3 Q1 1 2 3 4 5 6 7 8
IQR = Q3 – Q1
= 5 – 2
= 3
End of
Slide 6

7. Interquartile Range and Stem-and-Leaf (4/7)1 2 3 4 5
Stem
Leaf 1 2 6 Q1 1 3 3 5 6
Median
IQR = Q3 – Q1 4 4 5 7 7 9 9
= 38 – 13 2 3 4 6 8 Q3 5 7 7 9
= 25 5
End of
Slide 7

8. Interquartile Range - Box-and-Whisker (5/7)C D B A
A – Upper Extreme
B – Lower Extreme
C – Median
D – Upper Quartile – Q3
E – Lower Quartile – Q1
End of
Slide 8

9. Interquartile Range - Box-and-Whisker (6/7)2 4 6 8 10 12 14 16
IQR = Q3 – Q1
= 13 – 3
= 10
End of
Slide 9

10. IQR – 5 Number Summary (7/7)
Median Q3
Lower
Extreme 2 4 6 8 10 12 14 16
Upper
Extreme
Lower Extreme, Lower Quartile, Median, Upper Quartile, Upper Extreme
1, 3, 8, 13, 16
End of
Slide 10

11. Review Quiz: Please record your total score on the
Left side of your notebooks
Click on the Link below to start.