Communicating Through GraphsCommunicating Through Graphs

Column Graph Column Graph

Line Graph Line Graph

Sector or Pie Sector or Pie GraphGraph

What Do Graphs Show?What Do Graphs Show?

Column GraphColumn GraphEach line of information is in a column.Each line of information is in a column.

Each column touches the adjoining columns.Each column touches the adjoining columns.

Each column is the same width.Each column is the same width.

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Line graphLine graph A continuous line joins the dots.A continuous line joins the dots.

Best suits information which is continuous.Best suits information which is continuous.Eg.Eg. Information involving measurement (length, weight, etc) Information involving measurement (length, weight, etc)

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Step GraphsStep Graphs

Step graphs links 2 lines of information in a 90 Step graphs links 2 lines of information in a 90 degree relationship.degree relationship.

Often used to display information on sales or Often used to display information on sales or usage over a period of time.usage over a period of time.

Divided Bar GraphDivided Bar Graph

A divided bar graph A divided bar graph shows how the parts of shows how the parts of a particular bar make up a particular bar make up the whole.the whole.

As an example, the total As an example, the total number of shoes sold number of shoes sold may be divided into may be divided into how many were from how many were from the different the different distributors.distributors.

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1stQtr

2ndQtr

3rdQtr

4thQtr

C shoes

B shoes

A shoes

Conversion GraphsConversion Graphs

A A conversion graph changes one quantity to another. changes one quantity to another.

It is a useful tool for changing units of measurement, It is a useful tool for changing units of measurement, money, clothing sizes, etc.money, clothing sizes, etc.

Sector GraphSector Graph

(also known as Pie Graph) (also known as Pie Graph) Each sector shows the fraction of the total for each piece of data.Each sector shows the fraction of the total for each piece of data. Each sector is often shown as a percentage of the whole circle.Each sector is often shown as a percentage of the whole circle.

Results of Test

When to Use Which GraphWhen to Use Which GraphResults of Test

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emphasise?emphasise?

egeg Which occurred most often?Which occurred most often? What is the difference between What is the difference between

the data (range)?the data (range)?

Results of Test

How much information is needed to How much information is needed to be identified?be identified?egeg Is a visual appearance enough?Is a visual appearance enough? Is the pattern of results sufficient?Is the pattern of results sufficient?

Tables and GraphsTables and Graphs A graph will give a quick visual appearance of the information A graph will give a quick visual appearance of the information

contained in the table.contained in the table. However, a table will give you exact information whereas a graph may However, a table will give you exact information whereas a graph may

only give you approximations for the given information.only give you approximations for the given information.

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Results of a Maths Test

Marks Number of students

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Misleading GraphsMisleading Graphs

Graphs can be made to be very misleading by:Graphs can be made to be very misleading by:

Not starting the vertical axis at zero.Not starting the vertical axis at zero. Using an inappropriate or no vertical scale.Using an inappropriate or no vertical scale. Using 3-D shapes and comparing volumes.Using 3-D shapes and comparing volumes.

BibliographyBibliography Images provided by Microsoft Online Clip Art*Images provided by Microsoft Online Clip Art* http://office.microsoft.com/clipart/default.aspx?http://office.microsoft.com/clipart/default.aspx?

lc=en-us lc=en-us  A Math’s Dictionary for KidsA Math’s Dictionary for Kids http://www.teachers.ash.org.au/jeather/maths/http://www.teachers.ash.org.au/jeather/maths/

dictionary.htmldictionary.html Unit 3 Section 6: Conversion GraphUnit 3 Section 6: Conversion Graph http://www.cimt.plymouth.ac.uk/projects/mepres/http://www.cimt.plymouth.ac.uk/projects/mepres/

book7/bk7i3/bk7_3i6.htm book7/bk7i3/bk7_3i6.htm © Copyright NSW Department of Education and Training 2007.© Copyright NSW Department of Education and Training 2007. * Other names and brands may be claimed as the property of others.* Other names and brands may be claimed as the property of others.