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Prompt Cards

These two group activities use mathematical reasoning - one is numerical, one geometric.

Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

Exploring Wild & Wonderful Number Patterns

EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.

Dividing a Cake

Age 7 to 11
Challenge Level

It might be easier to work from this picture of the top of the cake with all possible cuts marked:

Cake top

You will find two copies of the cake top marked like this on this sheet.

What do all the numbers $0$ to $9$ add to? So what will the numbers on each of the three pieces add to?


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.