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Age 7 to 11
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  • Problem
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Why do this problem?

This problem gives practice in calculating, but it also offers a good point from which to open up a challenge and allow pupils freedom to explore (see the ideas below).

Key questions

What number could you try?
Will you need to try a bigger or smaller number next?

Possible extension

This sheet gives some possible extension ideas.

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A Right Charlie

Can you use this information to work out Charlie's house number?

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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.

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

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