Have you got SALT on your graph?

Learning Intention: Students will learn to draw a line graph to represent a data set, including the appropriate scale, axes, labels and title. They will also use technology to create a graph using the same data to compare the process and the product.

Success Criteria: A successful line graph will include the following:

  • lines drawn neatly with a ruler and greylead pencil or a digital graph with appropriate data
  • an appropriate scale to show the data clearly
  • clearly labelled and equal increments on both the horizontal and vertical axes
  • labels on each of the axes that identifies the appropriate data (time in years, population in 100,000’s for example)
  • a clear and accurate title that explains the purpose of the graph
  • Students may also be able to extrapolate the graph to make a prediction about future data.

“Every five years the Australian Bureau of Statistics (ABS) runs the Census of Population and Housing. This year 29 000 collectors will be part of a 43 000 strong Census workforce that will paint our national portrait in numbers. The Census is a questionnaire filled out by everyone who is in Australia on Census night, except foreign diplomats and their families. It’s so important that it’s mentioned in the Australian Constitution.

The Census counts the number of people in Australia, and information about them like what work they do, what education they have and the households they live in. This information helps decide where services such as hospitals, schools and roads will be built. The Census of Population and Housing is also used as the starting point to estimate the population of Australia, the states and territories and small communities.

This Census involves delivering 14.2 million Census forms to Australia’s 9.8 million households and then transporting and processing more than 46 million pages of data. Census is also changing with the times: 30% of the population are expected to fill out their forms online using eCensus.” Read more about the Census at “Maths by Email”.

The following task uses data taken from the results of the census to produce a line graph that shows the changes in the “Estimates of the Indigenous Australian Population since 1901”. Complete the graph with greylead and a ruler and answer the following questions:

  1. Give reasons for why a line graph is the most appropriate way to present this data.
  2. Explain why a histogram is an incorrect way to present this data.
  3. Look at the shape of the line in your graph. What sort of graph is this?
  4. Use extrapolation to estimate the Indigenous population for 2011.
  5. Do you think your estimate will be correct? Give reasons for your answer.

Now use Create-a-Graph, Excel, ChartGo or the Online Chart Tool to create another line graph using the same data. Compare your paper version with the digital version. In the comments section below let me know which tool you used and how the graphs compared. Which was easier and why? Which was a better product and why? Which tools would you prefer to use? How might you use these tools in the work place?


This is James’ graph, which includes SCALE, AXES, LABELS and a TITLE. Well done!

4 thoughts on “Have you got SALT on your graph?

  • August 8, 2011 at 12:01 pm
    Permalink

    I thought the computer was easier than the one on the paper.
    The Computer was better because it had a good graphs.
    I would prefer to put the year in on the left and the number on the right. The computer was better because it was the line graph was thin.

  • August 8, 2011 at 12:04 pm
    Permalink

    the online chart tool was fun and easy to use

  • August 8, 2011 at 12:05 pm
    Permalink

    I found the online chart tool much easier to use than the other computer chart makers. But i like doing it on paper because it is much easier.

  • August 8, 2011 at 12:07 pm
    Permalink

    it is easy on computer i used charttool

Leave a Reply

Your email address will not be published. Required fields are marked *