document.write( "Question 681767: Two dice are rolled. Find the probability that the sum was a 4 given that one of the numbers was a 1. \n" ); document.write( "
Algebra.Com's Answer #422777 by Edwin McCravy(20077)\"\" \"About 
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document.write( "Here are all 36 possible rolls with two dice:\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( "Since we are given that one of the numbers is a 1,\r\n" );
document.write( "we eliminate all the rolls that do not contain a 1,\r\n" );
document.write( "and leave only those that do:\r\n" );
document.write( "The ones containing a 1 are across the top and along the\r\n" );
document.write( "left side. There are 11 of them:\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)  \r\n" );
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document.write( "(3,1)  \r\n" );
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document.write( "(4,1)  \r\n" );
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document.write( "(5,1)  \r\n" );
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document.write( "(6,1) \r\n" );
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document.write( "Of those 11, the only ones that have sum 4 are (1,3) and (3,1)\r\n" );
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document.write( "That's 2 out of 11.\r\n" );
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document.write( "Answer: \"2%2F11\"\r\n" );
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document.write( "Edwin
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