A person starting with 646$ bets, wins three times and loses three times,
the wins and losses occurring in random order. The chance for a win is equal to the chance for a loss.
If each wager is for half the money remaining at the time of the bet, then the final result is:
27 \qquad \textbf{(B)}\text{ a gain of } 37 \qquad \\ \textbf{(D)}\text{ neither a gain nor a loss}\qquad \\ \textbf{(E)}\text{ a gain or a loss depending upon the order in which the wins and losses occur}$
Solution
If the person wins the bet, the person has of the previous amount. If the person loses the bet, the person only has of the previous amount.
Because of the Commutative Property, the order of multiplying the multipliers does not matter. Thus, the person walks away with dollars, so the person loses 37\boxed{\textbf{(C)}}$.
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