Can the positive integer n be written as the sum of two different positive prime numbers?

(1) n is greater than 3
(2) n is odd




all you need is one example that's a "yes" and one example that's a "no".
9 is a "yes", because it can be written as 2 + 7.
11 is a "no", because it can't be written as the sum of two positive primes at all. (because one of the primes would have to be even, that prime must be 2. that leaves the only possibility as 2 + 9, which doesn't work because 9 isn't prime.)

therefore, both statements together are still insufficient.


Ans : E