GMAT Club Tests | Re: M18-03

[quote="Bunuel"]Official Solution:


Statement (1) by itself is insufficient. S1 gives that\(x + y\) is divisible by 3. Consider\(x = 1\) ,\(y = 2\) (the answer is "no") and\(x = 3\) ,\(y = 3\) (the answer is "yes").

Statement (2) by itself is insufficient. S2 gives that\(x - y\) is divisible by 3. Consider\(x = 4\) ,\(y = 1\) (the answer is "no") and\(x = 6\) ,\(y = 3\) (the answer is "yes").

Statements (1) and (2) combined are sufficient. If both\(x + y\) and\(x - y\)