1. } Cumulative frequency “Quarter” QUARTILE:
 ‘running total’
The 25% boundary is
called the LOWER QUARTILE
The 50% boundary is known as the MEDIAN
The 75% boundary is
called the UPPER QUARTILE
“Quarter”
QUARTILE:
If we order the data and split it into 4 parts:
The first 25%
Between 25% and including 50%
Between 50% and including 75%
The last 25%
Then a QUARTILE is the name of each of
the boundaries 25%, 50% and 75%. }
of the data
The interquartile range looks at the middle 50% of the data
Upper Quartile (75%) – Lower Quartile (25%)

2. Using the graph, find the
Class 9a made a table showing the size of the students’ shoes in Year 9
Shoe Size
Frequency
Cumulative Frequency 3 1
3.5 4
4.5 5 13
5.5 6 12
6.5 7 8
7.5 2
8.5 9
9.5 10
How many people where in the class all together?
The cumulative frequency is a running total.
Fill in the table and then use the table to plot the graph.
Using the graph, find the
(1) median, (2) lower quartile, (3) upper quartile, (4) interquartile range.

3. The cumulative frequency is a
running total
In a certain school, 38 pupils took the maths SAT's exam (2006)
The results are shown in the table.
Level 5 6 7 8
Number of pupils 11 13 10 4
Cumulative frequency
Fill in the table and draw the graph
Using the graph, find the
median
lower quartile
upper quartile
interquartile range.

4. The year 9’s were ordered in years of age (in years).
13.2,13.2,13.2,13.2,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,3.3,13.3,13.3,
13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.3,13.4,13.4,13.4,
13.4,13.4,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,13.5,
13.5,13.5,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,13.6,
13.6,13.7,13.7,13.7,13.7,13.8,13.8,13.8.
Age
13.2
13.6
Number of pupils
Cumulative frequency
Copy and complete the table into your book
Draw a graph of the cumulative frequency in your book.
Using the graph, find the
(1) median, (2) lower quartile, (3) upper quartile, (4) interquartile range.

5. Fill in the table and draw the graph Using the graph, find the
Class 9a also made a table showing the showing their heart rate before exercise
Heart rate
Frequency
Cumulative 2 12
61 -70 20
71 -80 13 8 7 3
Fill in the table and draw the graph
Using the graph, find the
(1) median class, (2) lower quartile class, (3) upper quartile class.

6. Ext: The length of some leaves were measured