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## 'Ring a Ring of Numbers' printed from http://nrich.maths.org/

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.