__The Question__Using each of the non-zero digits only once, it is possible to construct a set of only prime numbers. The set {3, 41, 659, 827} is one possibility, with the sum of its members being equal to 1530.

What is the smallest possible sum that such a set of primes can have? Find one such set.

Just remember that the digits 1 to 9 inclusive must all be used but only once. Also note that you should not need to consult any tables of primes for the above question. However, such a list may well be useful for the extension exercises below.

__Extension Exercises__

If we restrict our required sets to those with just three 3-digit primes, find the two sets with the minimum and maximum possible sums. Again, use just the non-zero digits once each.

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