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Year 9 NAPLAN practice | Learn, see, try

Year 9: test the claim and the model

Build a model, test its assumptions and communicate a defensible conclusion. These examples connect algebra, critical reading and precise sentence editing without turning practice into a score prediction.

Adaptigo is an independent learning platform, not affiliated with or endorsed by ACARA. These original NAPLAN-style examples are not official test questions or results.

Read: Who answered the survey?

An online survey about extending park opening hours received eighty responses. Sixty respondents favoured later closing. The survey link appeared only in a local night-running group. A report described the result as evidence of interest among respondents, while noting that it did not establish the preferences of all park users.

You can reread this original passage while answering.

What to notice

A fixed charge is paid once; a rate applies repeatedly. Survey results describe respondents unless the sampling method supports a wider conclusion. Two complete clauses need a suitable boundary.

What to do

Define the unknown and write an expression for each cost. In reading, identify the group that actually supplied the evidence. When editing, test whether each side of a punctuation mark could stand as a sentence.

Why it works

A clear representation exposes hidden assumptions. Substituting an answer into both expressions checks equality. Naming the surveyed population prevents an unjustified generalisation. Recognising clauses makes punctuation choices explainable.

Work through an example

A club charges $5 plus $2 per visit. Model the cost of four visits.

  1. For v visits, write 5 + 2v dollars. The $5 fee occurs once.
  2. For four visits, calculate 5 + 2 × 4 = $13.
  3. Do not multiply the fixed fee by four: that would model a different charging arrangement.

A common mistake

A precise percentage does not remove selection bias. Even a correctly calculated proportion of responses cannot automatically describe people who were never reached by the survey.

A strategy to try

Use a substitution or counterexample to challenge your first answer. For a claim about all park users, ask whether a daytime visitor had the same opportunity to respond.

Try it now

Try three questions

No account is needed. These examples do not change saved learning progress. Choose an answer and check it for an explanation; you can try again.

Year 9 · Numeracy

1. Plan A costs $4 plus $3 per hour. Plan B costs $10 plus $2 per hour. After how many hours do they cost the same?
Help: a starting point

Write each total using the same number of hours h: 4 + 3h and 10 + 2h.

Help: the next step

Compare the fixed-fee gap with how much faster Plan A increases each hour.

Year 9 · Reading

2. Which conclusion is supported by the survey passage?
Help: a starting point

Separate the eighty respondents from all people who use the park.

Help: the next step

Check both the majority among respondents and the limitation on who received the link.

Year 9 · Conventions of Language

3. Which sentence correctly joins two complete clauses?
Help: a starting point

Test whether each statement has its own subject and complete verb.

Help: the next step

Choose punctuation that can join complete clauses without adding a conjunction.

For parents and carers

This set samples linear models, evaluation of evidence and sentence boundaries. Ask for the equation or passage detail that supports a choice, then discuss why a distractor fails. Explanations are useful even after correct answers: they reveal assumptions that may have been overlooked. Follow the domain links for additional reasoning examples and choose Year 9 in the full practice hub when ready.

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Open the learner hub and choose Year 9. Access to the full app follows its current guest and account options.

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