document.write( "Question 434512: conditional probability\r
\n" ); document.write( "\n" ); document.write( "a pair if dice is thrown. If it is known that one dice shows a 4, what probability that
\n" ); document.write( "a) the other dice shows a 5
\n" ); document.write( "b)the total of both the dice is greater than 7 \n" ); document.write( "
Algebra.Com's Answer #301011 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
conditional probability\r
\n" ); document.write( "\n" ); document.write( "a pair if dice is thrown. If it is known that one dice shows a 4, what probability that
\n" ); document.write( "a) the other dice shows a 5
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document.write( "Here are all 36 dice rolls\r\n" );
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document.write( "(1,1)  (1,2)   (1,3)  (1,4)   (1,5)  (1,6)\r\n" );
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document.write( "(2,1)  (2,2)   (2,3)  (2,4)   (2,5)  (2,6)\r\n" );
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document.write( "(3,1)  (3,2)   (3,3)  (3,4)   (3,5)  (3,6)\r\n" );
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document.write( "(4,1)  (4,2)   (4,3)  (4,4)   (4,5)  (4,6)\r\n" );
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document.write( "(5,1)  (5,2)   (5,3)  (5,4)   (5,5)  (5,6)\r\n" );
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document.write( "(6,1)  (6,2)   (6,3)  (6,4)   (6,5)  (6,6)\r\n" );
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document.write( "But since we are given that one of them is a 4, we\r\n" );
document.write( "can eliminate all the ones that don't have one of\r\n" );
document.write( "them a 4. That just leaves this reduced sample space\r\n" );
document.write( "of 11 rolls.\r\n" );
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document.write( "                      (1,4)   \r\n" );
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document.write( "                      (2,4)\r\n" );
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document.write( "                      (3,4)   \r\n" );
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document.write( "(4,1)  (4,2)   (4,3)  (4,4)   (4,5)  (4,6)\r\n" );
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document.write( "                      (5,4)   \r\n" );
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document.write( "                      (6,4)   \r\n" );
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document.write( "And therefore the probability that the other one is a 5\r\n" );
document.write( "is the probability of rolling one of the 2 that I have \r\n" );
document.write( "colored red below, out of the 11:\r\n" );
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document.write( "                      (1,4)   \r\n" );
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document.write( "                      (2,4)\r\n" );
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document.write( "                      (3,4)   \r\n" );
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document.write( "(4,1)  (4,2)   (4,3)  (4,4)   (4,5)  (4,6)\r\n" );
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document.write( "                      (5,4)   \r\n" );
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document.write( "                      (6,4)\r\n" );
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document.write( "So the answer is 2 out of 11 or 2/11.\r\n" );
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\n" ); document.write( "b)the total of both the dice is greater than 7
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document.write( "Since we are still given that one of them is a 4, we have the same\r\n" );
document.write( "reduced sample space, and I'll color the ones red which have a\r\n" );
document.write( "sum greater than 7\r\n" );
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document.write( "                      (1,4)   \r\n" );
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document.write( "                      (2,4)\r\n" );
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document.write( "                      (3,4)   \r\n" );
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document.write( "(4,1)  (4,2)   (4,3)  (4,4)   (4,5)  (4,6)\r\n" );
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document.write( "                      (5,4)   \r\n" );
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document.write( "                      (6,4) \r\n" );
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document.write( "That's 5 out of 11, or a probability of 5/11\r\n" );
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document.write( "Edwin
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