I'll take a run at the pearl problem......although I kind of like the idea that Anonymous had...snatching the bag and running!!!
I also believe that drawing all the pearls out of the bag, except one, is the correct strategy. Since, after any number of "even" draws, we never know how many white or black ones we have, we can never be sure that their totals are equal...if we could, "fabulous" Steve would soon be "broke" Steve.
Notice that after just 2 draws, there are 3 possibilities.....0W 2B, 1W 1B, 2W 0B ........Thus only one thing out of 3 wins for us.
Notice that after just 4 draws, there are 5 possibilities.....0W 4B, 1W 3B , 2W 2B, 3W 1B, 4W 0B........Thus only one thing out of 5 wins for us
And after 100 draws, again, only one thing out of 101 wins for us - 50W 50B, and 100 other combinations lose for us.
But, consider the scenario in which two pearls remain in the bag......If we draw either a white or black one on the next draw and a white one remains, we win. Thus, (draw white)(white remains) or (draw black)(white remains) are two winning scenarios.
But, if we draw either a black or white one and a black remains, we lose no matter what. Thus, out of the four remaining scenarios, 2 win for us and 2 lose, so we have a 50% chance of winning. And drawing all but one pearl out of the bag results in a greater chance of winning than stopping at any other point of even draws. Also note, that when we draw 2 pearls out ot the bag at first, we have a 33% chance of winning, but when two pearls remain, we are even money to win !!!
One final note....you could turn the tables on "fabulous" Steve and tell him that you will take one pearl out of the bag, and whatever remains in the bag is your "draw." Thus, if you draw a white one out, you win......otherwise, no.
That's my story, and I'm sticking to it!! (But, it might be incorrect, too......)