It's literally 25-28% women and 72-75% men in the Bay Area. These are the numbers I got from scraping OkC profiles that had words in them. There are more college educated men than there are women. There are more masters+ graduated men than there are bachelor+ women.
Even in NYC, there is something like 60% men compared to 40% women (and I'm being generous here).
From anecdotal evidence, you are also much more likely to get a boyfriend as a girl than a hookup on OkCupid compared to Tinder.
I asked several girls why they use Tinder, and they basically tell me that it is because they think that by having an intercourse, they can get the guy to like them more, leading to an instant relationship. But why not just start with an instant relationship and not go through something you don't want to do?