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Reasoning Foundations

Must-Be-True Conclusions

Must-Be-True Conclusions teaches a transferable deductive conclusions routine for selective and scholarship reasoning questions. Students learn the exact first move, the proof step, and the main trap to avoid before timed practice.

  • Separate what must be true from what could be true.
  • Chain two or more facts without reversing a rule.
  • Reject options that copy words but are not guaranteed.
Free sample lesson — reading only

Lesson overview

What this free sample teaches

Use the deductive conclusions routine to choose an answer and name the trap avoided.

Focus

  • Question family: deductive conclusions.
  • Core move: Start from a named fact, apply each rule in order, then test whether the answer could be false while every fact stays true.
  • Main trap: Choosing an option that sounds related but is only possible.

What gets tested

  • NSW/VIC/scholarship fit: NSW thinking skills and scholarship deductive reasoning.
  • Choosing the answer that is justified by the stated information.
  • Explaining why the strongest distractor fails.

Quick guide

  • Read the final question before the options.
  • Name the reasoning family and first move.
  • Use the stated facts or relationship, not outside knowledge.

Success criteria

  • Separate what must be true from what could be true.
  • Chain two or more facts without reversing a rule.
  • Reject options that copy words but are not guaranteed.

teach

Teach: Must-Be-True Conclusions

A must-be-true answer is locked in by the stated facts.

Must-Be-True Conclusions is a core reasoning lesson for NSW thinking skills and scholarship deductive reasoning. The aim is to prove the answer from the question, not to guess from topic familiarity.

A must-be-true answer is locked in by the stated facts. Students should treat this as a proof task: the answer must be supported by the facts, rules, data, relationship or argument in the question.

The routine is: Start from a named fact, apply each rule in order, then test whether the answer could be false while every fact stays true. This routine works across NSW, VIC and scholarship contexts because it focuses on the reasoning structure rather than the test label.

The common trap is Choosing an option that sounds related but is only possible. Strong students are often caught because the wrong answer is partly relevant. The fix is to name exactly why that option is not justified.

Reasoning family

deductive conclusionsIt tells you the first move.

Proof move

Start from a named fact, apply each rule in order, then test whether the answer could be false while every fact stays true.It links the answer to the question.

Distractor trap

Choosing an option that sounds related but is only possible.It explains why a tempting option fails.
Anatomy of deductive conclusions
  1. Question cluedeductive conclusions
  2. Core evidencefacts, rules, data, words or argument links supplied in the item
  3. Reasoning moveStart from a named fact, apply each rule in order, then test whether the answer could be false while every fact stays true.
  4. Trap checkChoosing an option that sounds related but is only possible.
  5. Answer shapeThe facts force ..., because ... then ...

The moveClassify the task, apply the routine, prove the answer, then reject the closest trap.

  • Separate what must be true from what could be true.
  • Chain two or more facts without reversing a rule.
  • Reject options that copy words but are not guaranteed.

show

Show: worked reasoning

Follow the proof move, then compare the trap.

Read the problem, name the reasoning family, and watch how the answer is proved.

Full problem

Choose the answer that is best supported.

Every student in the debating squad attends the speech workshop. Every student who attends the speech workshop receives a practice booklet. Tara is in the debating squad. Which conclusion must be true?

  1. Step 1 - Classify

    Name the job.

    This is a deductive conclusions question. The first move is: Start from a named fact, apply each rule in order, then test whether the answer could be false while every fact stays true.

    • Question familyNaming the family selects the right routine.

  2. Step 2 - Prove

    Use the stated information.

    Tara receives a practice booklet because squad member -> workshop -> booklet is a forced chain.

    • Proof moveThe answer is tied to the question, not to outside knowledge.

  3. Step 3 - Reject the trap

    Explain why the closest distractor fails.

    Tempting answer: Tara must be one of the best speakers.

    Why it fails: Choosing an option that sounds related but is only possible.

    • TrapA wrong answer can be relevant but still not justified.

compare

Compare: weak vs strong reasoning

See the difference between topic matching and proof.

The weak answer reacts to the surface topic. The strong answer proves the relationship or rule.

Weak answer

Tara must be one of the best speakers.

Strong answer

Tara receives a practice booklet because squad member -> workshop -> booklet is a forced chain.

First move

Weaker: Looks for a familiar word or number.Stronger: Uses the deductive conclusions routine.The routine keeps the answer tied to evidence.

Proof

Weaker: Gives a plausible answer without a clear link.Stronger: Shows how the stated information supports the answer.Reasoning questions reward justified conclusions.

Trap control

Weaker: Choosing an option that sounds related but is only possible.Stronger: Names why the distractor fails.Trap awareness improves transfer to mixed timed sections.

guide

Guide: checkpoint

Do one reasoning move before independent practice.

Answer in one sentence using the lesson's sentence starter.

All blue folders are locked. This folder is blue. What must be true?

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  • Separate what must be true from what could be true.
  • Chain two or more facts without reversing a rule.
  • Reject options that copy words but are not guaranteed.