MJ23 wrote:(1) insufficient can be any numbers

(2) (w+x+y)/3 = k
3k = w+x+y

if we rearange the formula in the questions it reads as 3k - (w+x+y)
substitute and you get (w+x+y) - (w+x+y)

2 is sufficient therefore answer is B

is this correct? it makes sense if the average of the three variables is K and the three variables are getting subtracted from K and added together, it should net out to 0

I guess you've changed statement 2 here to "the mean of w, x and y is k" instead of "the mean of w, x and y is 3" (as it was written in the original post above). With that change, the answer is certainly B, as you've shown. Since the OA is B, I'm guessing there was either a typo in the original post or in the source of the question, and I think your suggested rewrite is what the question was intended to be. It is certainly a more interesting question that way, since when Statement 2 reads as it does in the original post, it's pretty obvious that the answer is E, since we have no information about k and we need information about k.