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For younger learners

  • Early Years Foundation Stage

Clock Face

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Can you draw a straight line across the centre of a clock face so that the numbers on both sides of the line have the same total?

Can you do this in another way?

Can you draw two lines (like the hands of the clock) to divide the clock face so that the total of the numbers on one side of the lines is twice the total on the other side? Can you do this in another way?

Can you divide the clock face so that that the total on one side of the lines is five times more than the total on the other side? Can you do this in another way?

Can you draw two lines to divide the numbers so that the total of the numbers on each side of the lines are both multiples of six? In how many different ways can you do this?

Can you draw two lines so that the numbers on each side add to a prime number? Can you do this in another way?

Can you find any other interesting ways to group the numbers on a clock face by drawing two lines?

You might find this sheet useful for working on.


Click here for a poster of this problem.


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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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