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Ring of Numbers

Age 5 to 7
Challenge Level

Oli from Oakmeeds School began the first part of this question where we had to make odd differences between pairs of numbers.

You need odd, even, odd, even as odd + even make odd. Each pair has an odd and an even.

Rukmini from Hopscotch Nursery also said:

When the differences are all odd, the sums are all odd.

Rukmini then went on to say:

To make the differences even, you need the numbers 2, 4, 6, 8. Then the sums are also even.

Absolutely right - well done to both Oli and Rukmini. What about the order of the numbers 2, 4, 6 and 8 in the ring? Does it matter? I'll leave you all to ponder on that.
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.
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