Statistics

1
Statistics
Average (Mean), Range
Frequency Tables
Line Graphs
www.mathsrevision.com
Pie Charts
Constructing Pie Charts
2
Lesson Starter
Level 2
Q1. Write down the highest and lowest number in
this set of numbers.
52, 55, 62, 51, 59, 62, 52, 59, 61, 55
Q2. Add 2.34 5.03 7.2
www.mathsrevision.com
Q3. Find x to make this expression true.
3
Aims of the lesson
Level 2

• 1. We are learning the meaning of the keywords
• Mean and Range
• Calculate the mean and range for given data.

www.mathsrevision.com
4
Finding the range
The range of a set of data is a measure of how
the data is spread across the distribution.
To find the range we subtract the lowest value in
the set from the highest value.
When the range is small the values are similar
in size.
When the range is large the values vary widely
in size.
5
The range
Here are the high jump scores for two girls in
metres.
Joanna 1.62 1.41 1.35 1.20 1.15
Kirsty 1.59 1.45 1.41 1.30 1.30
Find the range for each girls results and use
this to find out who is consistently better.
Joannas range 1.62 1.15 0.47
Kirstys range 1.59 1.30 0.29
6
The mean
The mean is the most commonly used average.
To calculate the mean of a set of values we add
together the values and divide by the total
number of values.
For example, the mean of 3, 6, 7, 9 and 9 is
7
Two dice were thrown 10 times and their scores
were added together and recorded. Find the range
and mean for this data. 7, 5, 2, 7, 6, 12,
10, 4, 8, 9
Range
Mean
8
Extreme values and their effect on the mean
Here are some 1500 metre race results in minutes.
6.26 6.28 6.30 6.39 5.38 4.54
10.59 6.35 7.01

• Are there any extreme values?

• Will the mean be increased or reduced by the
  extreme value?

• Calculate the mean with the extreme value.

• Now calculate the mean without the extreme value.
  How much does it change?

It may be appropriate in research or experiments
to remove an extreme value before carrying out
analysis of results.
9
Average / Mean
Level 2
Now try Exercise 1 Ch9 (page 104)
www.mathsrevision.com
10
Lesson Starter
Level 2
Q1.
Q2. How long between 840am to 1.20pm
Q3. 36.9 x 6
www.mathsrevision.com
Q4. 34.7 x 100
Q5. Put these numbers in order
52, 55, 62, 51, 59, 62, 52, 59, 61, 55
11
Aims of the Lesson
Level 2
1. Understand the term Frequency
Table. 2. Construct a Frequency
Table. 3. Interpret information from Frequency
Tables.
www.mathsrevision.com
12
Frequency tables
Raw data can often appear untidy and difficult to
understand. Organising such data into frequency
tables can make it much easier to make sense of
(interpret) the data.
Data Tally Frequency







Sum of Tally is the Frequency
13
Frequency tables
Example 1. A tomato grower ideally wants his
tomatoes to have diameters of 60mm, but a
diameter ranging from 58mm to 62mm will be
acceptable. Organise the diameters given below
into a frequency table.
Lowest number
56
Highest number
62
14
Frequency tables
X
X
X
X
X
X
Diameter Tally Frequency
56
57
58
59
60
61
62
l
l
l
l
l
l
15
Frequency tables
Diameter Tally Frequency
56
57
58
59
60
61
62
3
4
9
13
10
5
4
16
Frequency Tables
Level 2
Now try Exercise 2 Ch9 (page 108) Q3 , Q5 Q9
www.mathsrevision.com
17
Lesson Starter
Level 2
Q1.
Q2. How long between 812am to 2.09pm
Q3. 75.9 x 7
www.mathsrevision.com

Find arrow value
Q4.
1300
1200
Q5. The answer to a question is 81. Write down
the question.
18
Aims of the Lesson
Level 2

• We are learning to interpret
• information from Line Graphs.
• 2. Construct a Line Graph.

www.mathsrevision.com
19
What are the Keypoints when creating a line graph
?
Title Labels Units Reasonable Scale
Line graphs
Line graphs are most often used to show trends
over time.
If the temperature in Aberdeen, in ºC, over a
12-hour period is plotted, the line graph shows
the temperature trend.
20
A hospital nurse recorded a patients temperature
every hour
Time (Hour) 6 am 7 am 8 am 9 am 10 am 11 am
Temperature oC 101 102 102.5 103 101 100.5
Temperature against Time
Title Labels Units Reasonable Scale
Temperature ?C
101
100
6
7
8
Time (Hours AM)
21
Line Graphs
Level 2
Now try Exercise 3 Ch9 (page 111) Q1 Q5
www.mathsrevision.com
22
Lesson Starter
Level 2
Q1.
Q2. 240 divided by 60
Q3. Simplify
www.mathsrevision.com
A circle is divided into 10 equal pieces. The
whole circle is 100. What value is one piece.
Q4.
Q5. The answer to a question is 60. Write down
the question.
23
Aims of lesson
Level 2
We are learning

• Work out the percentage of 1 slice.
• Interpret information from pie charts.
• Calculate the percentage values of a quantity.

www.mathsrevision.com
24
Pie Charts
Pie charts can be thought of as circle graphs.
Count the number of parts the circle is divided
into.
The percentage represented by each part is
Whole circle 100
100 ? number of parts
25
Pie Charts
A drinks machine dispenses 500 drinks on a
Monday. The information is displayed in the pie
chart. Use the information to find the number of
each drink sold.
Each part is 100 ? 10 10
26
Pie-Charts
Level 2
Now try Exercise 4 Ch9 (page 113)
www.mathsrevision.com
27
Starter Questions
www.mathsrevision.com
28
Pie Charts
Constructing Pie Charts
Learning Intention
Success Criteria

1. Find fractions of 360o.

• We are learning to construct an accurate
• Pie-Chart.

2. Use these fractions to construct a Pie Chart.
www.mathsrevision.com
29
Total
300
30
Rugby
31
(No Transcript)
32
Football
33
(No Transcript)
34
Cricket
35
(No Transcript)
36
Squash
Ice Hockey
37
(No Transcript)
38
(No Transcript)
39
Total
90
40
Total
90
Guitar
41
Total
90
42
Total
90
Violin
43
Total
90
Violin
Guitar
44
Total
90
Recorder
Violin
Guitar
45
Total
90
46
Total
90
Keyboard
Drum
47
Total
90
Guitar
Violin
Recorder
Keyboard
Drum
48
Drawing Pie Charts
Total
120
49
Drawing Pie Charts
Total
120
Vanilla
50
Drawing Pie Charts
Total
120
51
Drawing Pie Charts
Total
120
Banana
52
Drawing Pie Charts
Total
120
53
Drawing Pie Charts
Total
120
Chocolate
Strawberry
54
Drawing Pie Charts
Total
120