document.write( "Question 1151979: P(A)=0.39
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\n" ); document.write( "A and B are dependent.
\n" ); document.write( "P(A∣B)=0.385
\n" ); document.write( "Find P(A∩B)
\n" ); document.write( "Find P(A∪B)
\n" ); document.write( "Find P(B∣A) \n" ); document.write( "

Algebra.Com's Answer #773856 by ikleyn(52879) $\"\"$ $\"About$

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document.write( "P(A | B)  actually means and is the same as  P(A ∩ B)/P(B).\r\n" );
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document.write( "Therefore, the given  P(A | B) = 0.3855  means that  P(A ∩ B)/P(B) = 0.385.\r\n" );
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document.write( "Multiplying both sides of the last equality by P(B), you get\r\n" );
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document.write( "    P(A ∩ B) = 0.385*P(B) = 0.385*0.35 = 0.13475.\r\n" );
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document.write( "To find P(A U B), use the general formula\r\n" );
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document.write( "    P(A U B) = P(A) + P(B) - P(A ∩ B) = 0.39 + 0.35 - 0.13475 = 0.60525.    \r\n" );
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document.write( "Last step,   P(B|A) = P(B ∩ A) / P(A) = P(A ∩ B) / P(A) =  = 0.345513.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.   I answered all questions.\r
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\n" ); document.write( "\n" ); document.write( "If you want to see many similar solved problems and learn more on conditional probability, look into the lessons\r
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