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## 'Weekly Problem 34 - 2009' printed from http://nrich.maths.org/

I am standing behind five pupils who are signalling a five-digit number to someone on the opposite side of the playground. From where I am standing the number looks like 23456. What number is actually being signalled?

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.

*This problem is taken from the UKMT Mathematical Challenges.*

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