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For younger learners

  • Early Years Foundation Stage

Doubling Fives

Age 5 to 7
Challenge Level Yellow star
Primary curriculum
  • Problem
  • Getting Started
  • Teachers' Resources

This challenge is about doubling multiples of 5.

Pick a multiple of 5. Double it.

What is your answer? How many 10s is this?

Can you spot any patterns?

Can you explain the patterns?

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Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?

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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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