Interpret secondary data and media claims
A clear starting point, worked steps and space to practise.
Start here
A graph or report can be accurate about its sample without representing everyone. Check how the data was collected.
Ask “Who is missing?” A large sample can still be biased if the selection method excludes important groups.
1 Work through these steps
- Find the source, date and group studied.
- Check how people or items were selected.
- Read units, scales and missing information.
- State only conclusions the evidence supports.
2 Follow a worked example
A survey of 20 members of a football club finds 18 enjoy football. Does this show that 90% of all children enjoy football?
- 18/20 = 90% of this sample.
- The sample contains only football-club members.
- It does not represent all children, so the broader claim is not justified.
3 Try it yourself
Show each step on paper or open Working out. Then check the answer.
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A graph compares sales but gives no unit or time period. What needs checking before comparing?
Check answer 1
Answer: The sales unit and the time period.
Without them, the heights may compare different things or different lengths of time.
Scratchpad · Not saved
Working out
Draw with a finger, pen or mouse, or type your working below.
Your working stays on this page. It is not submitted or saved, and clears when you leave or reload.
Check your understanding
Explain the worked example in your own words. Say why the method works, not just what the answer is.
Skills and explanation links
Key ideas taught here
- A graph or report can be accurate about its sample without representing everyone. Check how the data was collected.
- Ask “Who is missing?” A large sample can still be biased if the selection method excludes important groups.
Method and checking
Optional recap: related Maths skills
These earlier examples revisit background skills. Start with the topic example and practice above.
Useful vocabulary
- data
- Information collected to answer a question.
- category
- A group used to organise data.
- mean
- A fair-share average.
- median
- The middle value when data is ordered.
Rules for these related skills
Check title, labels, key and scale first.
Use subtraction for 'how many more' questions.
Mean, median, mode and range each describe data in a different way.
Find the mode of 2, 3, 3, 5, 6.
- The mode is the value that appears most often.
- 3 appears twice.
- Mode = 3.
Find the median of 4, 9, 2, 7, 8.
- Order the data: 2, 4, 7, 8, 9.
- The middle value is 7.
- Median = 7.
Find the mean of 6, 8, 10, 12.
- Add values: 6 + 8 + 10 + 12 = 36.
- There are 4 values.
- 36 / 4 = 9. Mean = 9.
A graph shows 12 students chose soccer and 8 chose netball. How many more chose soccer?
- Compare the two categories.
- 12 - 8 = 4.
- 4 more students chose soccer.
More visual models and everyday examples
Each everyday example has its own information and model. Use its stated values rather than copying values from another question.
Concept example. The story examples below have their own diagrams.
Read the scale before comparing bars.
For parents and teachers
- Ask your child to explain the method aloud before writing the answer.
- Use a real-life context at home, such as shopping, cooking, sport scores, maps or timetables.
- Praise clear working and checking, not only speed.
- Encourage a quick diagram or table for word problems before calculating.
Practise choosing a method from the information in the question. The examples here are Pi Leo Academy learning activities. Official NAPLAN testing takes place in Years 3, 5, 7 and 9; a topic appearing in these notes does not mean it is tested in NAPLAN.
These notes provide guided examples and practice; they do not certify completion of every curriculum requirement.