document.write( "Question 1180354: For two events A and B, P(A) = 0.3 and P(B)=0.2. (a) If A and B are independent, then P(A|B) =
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Algebra.Com's Answer #810017 by ikleyn(52798) $\"\"$ $\"About$

You can put this solution on YOUR website!
For two events A and B, P(A) = 0.3 and P(B)=0.2. (a) If A and B are independent, then P(A|B) =
\n" ); document.write( "P(A∩B) =
\n" ); document.write( "P(A∪B) =
\n" ); document.write( "(b) If A and B are dependent and P(A|B) = 0.25,
\n" ); document.write( "then P(B|A) =
\n" ); document.write( "P(A∩B) =
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\n" ); document.write( "\n" ); document.write( " I will solve part a), ONLY.\r
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document.write( "First, P(A ∩ B) = P(A)*P(B) = 0.3*0.2 = 0.06  (since A and B are independent).\r\n" );
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document.write( "Second,  P(A U B) = P(A) + P(B) - P(A ∩ B) = 0.3 + 0.2 - 0.06 = 0.44.\r\n" );
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document.write( "Third, P(A | B) =  =  = 0.3.\r\n" );
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One and ONLY ONE problem/question per post.

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\n" ); document.write( "\n" ); document.write( "Edwin expressed \"a favor\" in my address - - - so, I will express my favor in his address, mutually.\r
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\n" ); document.write( "\n" ); document.write( "Ignore his solution: it is INCORRECT:\r
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\n" ); document.write( "\n" ); document.write( "             It is incorrect, because it is based on your incorrect formulation of the part b).\r
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\n" ); document.write( "\n" ); document.write( "             The event A and B must be INDEPENDENT - - - while your formulation \r
\n" ); document.write( "\n" ); document.write( "            calls them \"DEPENDENT\" - - - clearly, directly, explicitly and incorrectly.\r
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\n" ); document.write( "\n" ); document.write( "            And Edwin NEITHER disproved NOR corrected it . . . \r
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