document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1132895>Question 1132895</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One of the wagers in the game of roulette is to place a bet that the ball will land on a black number. (Eighteen of the numbers are black, 18 are red, and two are green.) If the ball lands on a black number, the player wins the amount of his bet. If a player bets $4, find the player's expectation. (Round your answer to two decimal places.) </SPAN>\n" );
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document.write( "E = (payoff)*Pr(win) - (wager)*Pr(lose)<BR>\n" );
document.write( "  =  4*18/(18+18+2) - 4*(18+2)/(18+18+2)<BR>\n" );
document.write( "   = 72/38 - 80/38<BR>\n" );
document.write( "   = -8/38<br>\r<BR>\n" );
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document.write( "Since this is a negative expectation, the player is expected to LOSE (4/19) dollars or about $0.21 per play.   </SPAN>\n" );
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