Apparently, Yahoo! is acquiring Tumblr for $1.1 billion in cash. If you own shares of Yahoo, how much did you just fork over for the blog site? Interestingly enough, Yahoo has 1.08 billion shares outstanding, an amount almost equal to the purchase price of Tumblr. If you own 100 shares of Yahoo, then you essentially just wrote a check from a business account for $100 to be the owner of Tumblr.