Maths: Grade 4
Data Handling: Collecting, Organising and Recording Data
COLLECTING, ORGANISING AND RECORDING DATA
The collecting, organising and interpreting of data (information) is calledstatistics.
It involves the following steps:
•
•
•
•
•
Collecting the data
Organising the data
Recording the data
Displaying the data
Interpreting the data
The process lets us take large amounts of information and make it
easier to understand.
Collecting Data
Information or data can be collected in a variety of ways:
Asking Questions
You can ask questions verbally to gather data, so to gather data on children’s hair colour,
in a class, you could ask: What is your hair colour? The answers can then be organised
into a table or a graph.
Written Questionnaires or Surveys
Example
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Data Handling: Collecting, Organising and Recording Data
Organising Data
Now you have collected the data, you need to organise or group it so that it can be
interpreted or analysed.
There are several ways of recording the data:
Using Tally Marks
These can be used to keep count of something.
To tally, you mark a line for each unit counted and then cross through when 5 units are
covered.
Example
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Maths: Grade 4
Data Handling: Collecting, Organising and Recording Data
Using a Table
A frequency table can be used to organise the data. This shows the number in each
category.
Example
The table below shows the number of children in the class with different hair colours:
Hair Colour
Blonde
Number of Children
5
Black
10
Brown
10
You could even add another column to show the breakdown of hair colour between boys
and girls:
Hair Colour
Blonde
Boys
1
Girls
4
Black
6
4
Brown
5
5
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Maths: Grade 4
Data Handling: Collecting, Organising and Recording Data
Displaying Data
Data can be displayed in a visual form in the following ways:
Bar Graph
Information from the tally marks or frequency table can be used to draw a bar graph.
This displays the data on a graph, which makes it easy to read and understand.
Bars of different lengths are drawn to show the number or frequency of the data. Each bar
represents a set of data, in our example, hair colour. The height of each bar clearly shows
how many children have different hair colour.
We can see from the above that the height of each bar shows the number of children with
each hair colour.
The following axes are used on a bar graph:
Horizontal axis – in this example, hair colour.
Vertical axis – in this example, number of children.
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Maths: Grade 4
Data Handling: Collecting, Organising and Recording Data
How to draw a bar graph:
You will need: paper or graph paper, a pencil, information from the tally box or
frequency table.
1. Choose a suitable scale for your data, according to the highest and lowest
numbers in your tally box or frequency table. In our example the highest number
is 10.
2. Draw the vertical axis, give it a name and number your graph with an appropriate
scale.
3. In our example, number of children.
4. Draw the horizontal axis and give it a name. In our example, hair colour.
5. Take the number for the 1st set of data (blonde hair) and find the correct place on
the vertical axis. Draw a line on the 5 mark to show this.
6. Do the same for the 2nd and 3rd set of data – black and brown hair.
7. Colour in the bars to make it easy to read.
Pie Chart
A pie chart is a circular graph that is divided into pieces. Each piece shows the size of the
related piece of information that makes up the whole.
Example
The pie chart below shows how 20 Grade 4 learners travel to school.
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Maths: Grade 4
Data Handling: Collecting, Organising and Recording Data
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We can see that 4 of learners travel by car.
1
The number of learners travelling by car is 4 of 20 = 5.
1
We can see that 4 of learners also walk to school.
The number of learners walking to school is also 5.
1
We can also see that 2 of the 20 learners travel by public transport.
1
So, the number of learners travelling by public transport is 2 of 20 learners = 10.
Pictogram
The picture above is called a pictogram. In a pictogram, we use pictures to represent
quantities.
A picture can represent one thing or a number of things. It is similar to a bar graph, but it
uses pictures or images to represent the units.
A pictogram can also be called a pictograph or a picture graph.
Interpreting Data
Once the data has been displayed in a bar graph or a pictogram, it is easy to interpret.
In the hair colour example, we can see that half as many children in the class have blonde
hair as black or brown hair.
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