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DM overview

Turn rules and information into the one conclusion you can defend.

Guide page1 of 7

DM tests whether a conclusion follows from the rules and data you are given. Real-world likelihood is irrelevant — only the stated information counts.

35questions
37 mintotal time
MCQsingle best answer
Yes/No5-statement sets (partial credit)

The one rule — translate before you judge

Turn every premise into a clear structure (arrow, set, grid or table) before testing a conclusion. Two question types, one habit:

Must be true

True in every valid arrangement — one counterexample defeats it.

Could be true

True in at least one valid arrangement.

Yes / No sets

Judge each statement independently. A correct set earns two marks; four of five earns one.

Timing

1

Identify the question type before drawing anything.

2

Fixed rules first — add constraints one at a time.

3

Use counterexamples to defeat 'must' claims quickly.

4

Flag with your diagram visible so you can return efficiently.

Traps to know

Converse error

A → B does not mean B → A.

Existence assumption

'All A are B' does not prove any A exist.

Possibility as certainty

One valid arrangement proves could, not must.

Irrelevant argument

A true or emotional statement can still fail to support the proposal.

Hidden denominator

A percentage can flip in meaning when the group size changes.

Question types

Go deeper into each format.

Question skills

DM

Syllogisms

Decide what must follow from category or conditional premises.

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DM

Interpreting Information

Judge conclusions from tables, charts and short reports.

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DM

Venn Diagrams

Reason about inclusion, overlap, exclusion and counts.

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DM

Arguments & Assumptions

Judge whether a reason genuinely supports a proposal.

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DM

Logic Puzzles

Build an arrangement that satisfies every condition.

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DM

Probability

Calculate single, combined and conditional outcomes.

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