(Don't get mad at me, women, because the emphasis here is on "play".) It seems to be commonly accepted that women "play dumb" when they're around men, and many women even get frustrated with themselves for not demonstrating how intelligent they really are. My thought had always been that a woman would pretend to be dumb in order to make a man she found attractive feel appreciated and smart. That's fine as far as it goes, but Nikolas Lloyd suggests that acting dumb and inviting men to talk is the human female form of the "lek".
Jackie, by asking this stupid question, is inviting the men to a lek. A lek is a term used by biologists to refer to a display by many males in one place, from which females might choose a male to mate with. It is a behaviour used by many species of bird, generally those where the male is gaudy, and the females drab. The men around the table now each get invited or lured to participate. The party’s host (or, more likely, hostess) might make sure that everyone gets to speak. The more able male speakers might taunt the less able into speaking, so as to offer a contrast with their abilities. Each man then offers his answer to her stupid question, and will seek to impress her, and show her that he know more than she does. She will not break the spell by admitting to any knowledge. She wants to hear what all the men have to say under equal conditions, before judging them. She and the other women around the table will all get to hear all the men, and so the best thing that they can do is shut up and listen.
And thus, the women get to discover which men are smart, which are arrogant, which are outgoing, which are polite, and so forth. These traits help the women determine whom they want to mate with.
It is interesting to consider whether this "lek instigation" by women -- likely subconsious -- has implications for how women interact with men in other settings, such as business meetings. Since most women "play dumb" regardless of their intentions at the time, it may be that they then later reclassify this mating instinct as "shyness" or "intimidation" without understanding what's really going on. An instinct that helps women identify good mates might hinder them in other contexts.