document.write( "Question 471066: One thousand raffle tickets are sold for $5.00 each. One grand prize of $800 and two consolation prizes of $100 each will be awarded. Jeremy purchases one ticket. Find his expected value. Show your work for full credit.
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document.write( " (Points : 7) \n" );
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Algebra.Com's Answer #323120 by ccs2011(207)![]() ![]() You can put this solution on YOUR website! expected value is a weighted average of all possible outcomes. \n" ); document.write( "Let p be the probability of an outcome. \n" ); document.write( "Let g be the net gain of an outcome. \n" ); document.write( "The expected value of an outcome is the product of p and g. \n" ); document.write( "E = p*g \n" ); document.write( "In this problem there are 3 outcomes: win grand prize, win consolation prize, win nothing. \n" ); document.write( "His total expected value of the raffle ticket is the sum of the expected values from each outcome. \n" ); document.write( "Outcome 1: win grand prize \n" ); document.write( "there are 1000 tickets but only 1 winner, so p = 1/1000 \n" ); document.write( "you win $800 but it cost you $5, so g = 795 \n" ); document.write( "Outcome 2: win consolation prize \n" ); document.write( "there are 1000 tickets and only 2 winners, so p = 2/1000 or 1/500 \n" ); document.write( "you win $100 but it cost you $5, so g = 95 \n" ); document.write( "Outcome 3: win nothing \n" ); document.write( "1000-2-1=997, this means 997 tickets do not win, so p = 997/1000 \n" ); document.write( "you win 0 but it cost you $5, so g = -5 \n" ); document.write( "Now compute Expected Value (EV): \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "Therefore for every raffle ticket you buy, you should expect to lose $4. \n" ); document.write( "Another way of looking at it is you expect to win $1 for every ticket you buy, but since each one costs $5 its not a very worthwhile investment. \n" ); document.write( " |