document.write( "Question 475455: Two digits are randomly selected without repetition, compute probability tha their sm is odd... also that their product is odd \n" ); document.write( "

Algebra.Com's Answer #326082 by Edwin McCravy(20060) $\"\"$ $\"About$

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For the sum being ODD is solved here:\r
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document.write( "EVEN × EVEN = EVEN\r\n" );
document.write( "EVEN × ODD = EVEN\r\n" );
document.write( "ODD × EVEN = EVEN\r\n" );
document.write( "ODD × ODD = ODD\r\n" );
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document.write( "So to have their product odd, they have to both be odd.\r\n" );
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document.write( "The digits are\r\n" );
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document.write( "0,1,2,3,4,5,6,7,8,9\r\n" );
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document.write( "5 are ODD and 5 are EVEN.\r\n" );
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document.write( "After we have chosen the first digit, there are only 9 digits \r\n" );
document.write( "left to choose from:\r\n" );
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document.write( "P[(odd 1st AND odd 2nd) =\r\n" );
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document.write( "AND indicates multiplication:\r\n" );
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document.write( "  P(odd 1st)×P(odd 2nd) =\r\n" );
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document.write( "       (5/10)(4/9) \r\n" );
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document.write( "       (1/2)(4/9) \r\n" );
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document.write( "          4/18\r\n" );
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document.write( "           2/9   \r\n" );
document.write( "          \r\n" );
document.write( "Edwin

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