Live Problems - Stage 3, 4 & 5

Secondary Toughnutslive

Age 11 to 18 Challenge Level:

These secondary problems have not yet been solved. Can you be the first?

Your Number Is...live

Age 7 to 14 Challenge Level:

Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?

Twisting and Turninglive

Age 11 to 14 Challenge Level:

Take a look at the video and try to find a sequence of moves that will untangle the ropes.

More Twisting and Turninglive

Age 11 to 16 Challenge Level:

It would be nice to have a strategy for disentangling any tangled ropes...

All Tangled Uplive

Age 14 to 18 Challenge Level:

Can you tangle yourself up and reach any fraction?

Your Number Was...live

Age 11 to 14 Challenge Level:

Think of a number and follow my instructions. Tell me your answer, and I'll tell you what you started with! Can you explain how I know?

Neighbourly Additionlive

Age 7 to 14 Challenge Level:

I added together some of my neighbours house numbers. Can you explain the patterns I noticed?

The Number Jumblerlive

Age 7 to 14 Challenge Level:

The Number Jumbler can always work out your chosen symbol. Can you work out how?

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.
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NRICH is part of the family of activities in the Millennium Mathematics Project.