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For younger learners

  • Early Years Foundation Stage

Take Three Numbers

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

Take Three Numbers printable sheet

Choose any two odd numbers and one even number, such as 3, 5 and 2.

How would you like to represent these numbers?

Try adding them together and draw/make the representation of their sum.

What do you notice about the answer?

Look closely at your model.

Would it work in exactly the same way if you used different numbers but still two odds and one even?

Can you use your example to prove what will happen every time you add two odd numbers and one even number?

See if you can explain this to someone else. Are they convinced by your argument?

Once you can convince someone else, see if you can find a way to show the argument on paper. You might draw something or take a photo of things you have used to prove that your result is always true from your example.

Related Collections

  • Back to NRICH at Every Stage resources

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Consecutive Numbers

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

Roll These Dice

Roll two red dice and a green dice. Add the two numbers on the red dice and take away the number on the green. What are all the different possible answers?

Domino Square

Use the 'double-3 down' dominoes to make a square so that each side has eight dots.

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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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