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Slide enlarger

ENIGMA represents a six-digit number in which the digits are all different and non-zero.

When EN slides from the front to the back, the resulting six-digit number, IGMAEN, is 20 per cent larger than ENIGMA.

What is ENIGMA?

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 3 November 2010. The Editor’s decision is final. Please send entries to Enigma 1615, ¿ìè¶ÌÊÓƵ, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address).

Answer to 1609 I remember it well: The number is 5468

The winner Brent Jackson of Auckland, New Zealand