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## 'One to Fifteen' printed from http://nrich.maths.org/

Thank you for all your solutions to this
problem. Many of you sent in a way of completing the challenge -
unfortunately there are too many to name you all. Lu-Lu, James and
Sam from St Nicolas C of E Junior School, Newbury commented:

We found lots of different solutions. We noticed that 1 and 15 had
less consecutive numbers than the other numbers. 1 has only 2 and
15 has only 14. The other numbers, 2, 3, 4, ......,12 and 13 have
two consecutive numbers each. So it's best to put 1 and 15 in the
middle, but we did find other solutions as well.

What a sensible way to start the problem
- well done to you three! Many pupils from Eastwood Primary School
sent us solutions. Rajal explained:

We looked at all the numbers then we started with 11, 15 and 13.
Then we did the numbers 14, 1, 6, 10 and 3. Then we made sure that
no consecutive numbers were there. This allowed us to put most of
the numbers in place but a few of the last ones caused problems. We
played around with these until they all were correct.

This is another good way to approach the
problem - using a bit of trial and improvement. Here is Rajal's
solution:

Luke and Daniel from Whingate Primary in Leeds
sent a slightly different solution:

As Lu-Lu, James and Sam say, there are
many different ways to complete this problem - perhaps you have
found one which is not the same as these two - but thank you to
those of you who gave help with good ways of going about it. That's
what NRICH is looking for!