Those questions are not remotely equivalent. I suppose as a second order implication, if you assume that the average man is not very good at math, you could also assume that the average women is really not very good at math, but obviously both the male and female distributions have people above their respective means. In any case, "Why and how do women suck at math" sounds to me like "Why do all women suck at math," not like "Why does the average woman suck at math," even if the latter question was based on an accurate presupposition.