document.write( "Question 715068: If we have a box containing slips of paper with the following numbers: 3,5,8,10,13,23,30,36,21,34 and a slip of paper is selected and not replaced. What are the following probabilities:
\n" ); document.write( "p(multiple of 3 then multiple of 5)
\n" ); document.write( "P(prime then odd)
\n" ); document.write( "P(prime then even then 21)
\n" ); document.write( "P(odd then 10 then 30)\r
\n" ); document.write( "\n" ); document.write( "How do you deal with numbers that share a common property (I.e. multiple of 5 and three, or odd and prime) in an independent probability problem like this one.
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Algebra.Com's Answer #439211 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
If we have a box containing slips of paper with the following numbers: 3,5,8,10,13,23,30,36,21,34 and a slip of paper is selected and not replaced. What are the following probabilities:
\n" ); document.write( "p(multiple of 3 then multiple of 5) =
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document.write( "P(one of these 4, {3,30,36,21) AND THEN one of these 3 {5,10,30}.\r\n" );
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document.write( "This breaks into two cases each with a different probability:\r\n" );
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document.write( "Case 1:  We draw the 30 first \"1%2F10\"\"%22%22%2A%22%22\"\"2%2F9\" = \"2%2F90\"\r\n" );
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document.write( "Case 2:  We don't draw 30 first \"3%2F10\"\"%22%22%2A%22%22\"\"3%2F9\" = \"9%2F90\"\r\n" );
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document.write( "Desired probability = \"2%2F90%2B9%2F90\" = \"11%2F90\" \r\n" );
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\n" ); document.write( "P(prime then odd)
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document.write( "P(one of these 4, {3,5,13,23) AND THEN one of these 5 {3,5,13,23,21}.\r\n" );
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document.write( "This breaks into two cases each with a different probability:\r\n" );
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document.write( "Case 1:  We draw the 21 second \"4%2F10\"\"%22%22%2A%22%22\"\"1%2F9\" = \"4%2F90\"\r\n" );
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document.write( "Case 2:  We don't draw 21 second \"4%2F10\"\"%22%22%2A%22%22\"\"3%2F9\" = \"12%2F90\"\r\n" );
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document.write( "Desired probability = \"4%2F90%2B12%2F90\" = \"16%2F90\" = \"8%2F45\"\r\n" );
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\n" ); document.write( "P(prime then even then 21)
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document.write( "p(one of these 4, {3,5,13,23) AND THEN one of these 5 {8,10,30,36,34} and THEN {21}\r\n" );
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document.write( "None of these have a common property so it is not necessary to break into\r\n" );
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document.write( "Desired probability = \"4%2F10\"\"%22%22%2A%22%22\"\"5%2F9\"\"%22%22%2A%22%22\"\"1%2F8\" = \"20%2F720\" = \"1%2F36\"\r\n" );
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\n" ); document.write( "P(odd then 10 then 30)
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document.write( "p(one of these 5, {3,5,13,23,21}. AND THEN {10} AND THEN {30}\r\n" );
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document.write( "None of these have a common property so it is not necessary to break into\r\n" );
document.write( "cases:\r\n" );
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document.write( "Desired probability = \"5%2F10\"\"%22%22%2A%22%22\"\"1%2F9\"\"%22%22%2A%22%22\"\"1%2F8\" = \"5%2F720\" = \"1%2F144\"\r\n" );
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\n" ); document.write( "How do you deal with numbers that share a common property (I.e. multiple of 5 and three, or odd and prime) in an independent probability problem like this one.
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document.write( "We have to break them into two or more cases, cases where we choose ones\r\n" );
document.write( "with the common properties, and cases where we don't.  Then add the probabilities.\r\n" );
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document.write( "Edwin
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