document.write( "Question 1163268: Find P(A and B) if;
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Algebra.Com's Answer #787309 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "(i)  Use the general formula of the Probability theory\r\n" );
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document.write( "         P(A or B) = P(A) + P(B) - P(A and B).\r\n" );
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document.write( "     Substitute the given data to the formula\r\n" );
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document.write( "          =  +  - P(A and B).\r\n" );
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document.write( "     It gives you\r\n" );
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document.write( "          P(A and B) =  =  =  = .     ANSWER\r\n" );
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document.write( "(ii)  The given equality  P(A|B) =   means, by the definition of the conditional probability, that\r\n" );
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document.write( "          P(A and B)/P(B) = .\r\n" );
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document.write( "      It implies that\r\n" );
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document.write( "           P(A and B) =  =  = .     ANSWER\r\n" );
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document.write( "      Notice that the given value  P(A) =   is IRRELEVANT to the solution of the part (ii).\r\n" );
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\n" ); document.write( "\n" ); document.write( "If you want to see many other similar solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Elementary operations on sets help solving Probability problems \r
\n" ); document.write( "\n" ); document.write( "    - Elementary operations on sets help solving Probability problems - REVISITED \r
\n" ); document.write( "\n" ); document.write( "    - Using general probability formulas for a union or intersection of events \r
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