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Six factors

Harry chose two 2-digit numbers and added them together to create a third 2-digit number. Each of the three numbers was the product of two primes; the six primes were all different.

He then transposed the unit digits of his first two numbers to create two new numbers, which he added together to create the same third number as before. Once again each of the three numbers was the product of two primes, the six primes all being different.

What was the ‘third number’ common to both sums?

WIN £15 will be awarded to the sender of the first correctanswer opened on Tuesday 28 April. The Editor’s decision is final. Please send entries to Enigma 1538, New Å®ÉúСÊÓƵ, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address).

Answer to 1532 Just reflecting: The small angle, rounded to the nearest degree, was 9 degrees

The winner Chris Kaye of Hemel Hempstead, Hertfordshire, UK