Reasoning, convincing and proving

There are 514 NRICH Mathematical resources connected to Reasoning, convincing and proving

problem

Favourite

Polygon rings

Age

11 to 14

Challenge level

Join pentagons together edge to edge. Will they form a ring?

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Favourite

Gabriel's problem

Age

11 to 14

Challenge level

Gabriel multiplied together some numbers and then erased them. Can you figure out where each number was?

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Favourite

Multiple surprises

Age

11 to 16

Challenge level

Sequences of multiples keep cropping up...

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Favourite

Fibonacci surprises

Age

11 to 14

Challenge level

Play around with the Fibonacci sequence and discover some surprising results!

problem

Favourite

Puzzling place value

Age

14 to 16

Challenge level

Can you explain what is going on in these puzzling number tricks?

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Favourite

Six numbered cubes

Age

7 to 11

Challenge level

This task combines spatial awareness with addition and multiplication.

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Favourite

Six ten total

Age

7 to 11

Challenge level

This challenge combines addition, multiplication, perseverance and even proof.

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Favourite

Multiplication arithmagons

Age

14 to 16

Challenge level

Can you find the values at the vertices when you know the values on the edges of these multiplication arithmagons?

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Favourite

Reversals

Age

11 to 14

Challenge level

Where should you start, if you want to finish back where you started?

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Favourite

Pythagoras perimeters

Age

14 to 16

Challenge level

If you know the perimeter of a right angled triangle, what can you say about the area?

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For younger learners

Reasoning, convincing and proving

Polygon rings

Gabriel's problem

Multiple surprises

Fibonacci surprises

Puzzling place value

Six numbered cubes

Six ten total

Multiplication arithmagons

Reversals

Pythagoras perimeters