The prize, as it has been every week for weeks and weeks, is access to the coveted PWN the SAT Math Guide Beta. If you wanna win, you have to comment in such a way that I can contact you. Preferably using Facebook, Twitter, or Gmail.
A warning: this one is pretty tough.
In a hand in his weekly poker game, Mike won money from both John and Sean. Mike's percent gain on the hand was equal in magnitude to John's percent loss. John bet twice as much as did Sean. Mike and John together held $200 in chips before the hand began. If Sean bet $20 in chips on the hand, what was Mike's chip total after the hand was over?Good luck!
UPDATE: Nobody got this yet, so I'm gonna leave it up for now unanswered. If you solve it, book access is yours.
SECOND UPDATE: OK, Eowyn got it. Nice. Solution below the cut.