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Two Numbers Under the Microscope

This investigates one particular property of number by looking closely at an example of adding two odd numbers together.

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Odd Times Even

This problem looks at how one example of your choice can show something about the general structure of multiplication.

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Walking Round a Triangle

This ladybird is taking a walk round a triangle. Can you see how much he has turned when he gets back to where he started?

A Bag of Marbles

Stage: 1 Challenge Level: Challenge Level:2 Challenge Level:2

You could print off this sheet which has pictures of the marbles on. If you cut them out, you could move them around and group them as you work on the problem.
Is there only one marble that sparkles when rolling and is dark inside?
How do you know?

The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities can be found here.
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NRICH is part of the family of activities in the Millennium Mathematics Project.