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Deductive reasoning

In deductive reasoning, general principles are applied to specific instances. If the original premises are true, conclusions based on deductive reasoning are also true. For example:


Even numbers are integers that can be arranged as pairs.
I can arrange six blocks as three pairs.
So six is an even number.


Applying a rule, formula or theorem is a form of deduction.


The sum of the angles of any triangle is 180°.
This shape is a triangle.
The sum of its angles is 180°.


Max's Statements is an activity involving deduction to try with students from years 5–9.