document.write( "Question 1103446: A) We roll a pair of dice. If the sum of the dice is 7, you pay $30. If the sum is not 7, I pay you the number of dollars indicated by the sum of the dice. What is your expected value?\r
\n" ); document.write( "\n" ); document.write( "B)What is the price that you should pay to play the game that would make the game fair?
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Algebra.Com's Answer #718143 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "The expected value is found by adding all the products of the probability of each outcome and the value of each outcome.

\n" ); document.write( "1/36 probability of getting a 2; 2*1/36 = 2/36
\n" ); document.write( "2/36 probability of getting a 3; 3*2/36 = 6/36
\n" ); document.write( "3/36 probability of getting a 4; 4*3/36 = 12/36
\n" ); document.write( "4/36 probability of getting a 5; 5*4/36 = 20/36
\n" ); document.write( "5/36 probability of getting a 6; 6*5/36 = 30/36
\n" ); document.write( "6/36 probability of getting a 7; 7*-30/36 = -210/36
\n" ); document.write( "5/36 probability of getting a 8; 8*5/36 = 40/36
\n" ); document.write( "4/36 probability of getting a 9; 9*4/36 = 36/36
\n" ); document.write( "3/36 probability of getting a 10; 10*3/36 = 30/36
\n" ); document.write( "2/36 probability of getting a 11; 11*2/36 = 22/36
\n" ); document.write( "1/36 probability of getting a 12; 12*1/36 = 12/36

\n" ); document.write( "The expected value is the sum of all those fractions, which is exactly 0.

\n" ); document.write( "So the game is fair at the current price.
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