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Challenge Response 70


How many ways?

In no way, let's see why:
If the number 497 is the sum of two natural numbers, as it is odd, it must be obtained from the sum of an even and an even (since the sum of two even is the same as the sum of two odd) .

So our problem is to get two prime numbers (one even and one odd), which together give the result 497. Since the only even prime number is 2, we already have the first parcel, which forces the second parcel to be equal to 495 (for the sum give 497). Since 495 is not prime (ends in 5, so is multiple of 5), our problem has no solution.

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