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  • Early Years Foundation Stage

A Conversation Piece

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
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A Conversation Piece


Divide 6 469 693 230 by the first ten prime numbers and you'll get the most beautiful and most magic of all numbers. What is it?

Why do this problem?

This problem offers a lot of practice of division as well as revision of ideas about prime numbers in a situation in which children want to get to the answer - much more fun than a page of calculations but just as much practice. It requires a calculator unless someone really relishes long division!

Key questions

Have you made a list of the first ten prime numbers?
Remember that $1$ is not a prime number.
Which number are you going to divide by first?
How will you know whether you have divided by that number already?

Possible extension

Learners who find it easy could be encouraged to invent their own similar problems which will give them practice with multiplication as well as division.
 

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Dice and Spinner Numbers

If you had any number of ordinary dice, what are the possible ways of making their totals 6? What would the product of the dice be each time?

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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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