document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1203813>Question 1203813</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An urn contains 4 white balls and 6 red balls. A second urn contains 6 white balls and 4 red balls. An urn is selected, and a ball is randomly drawn from the selected urn. The probability of selecting the first urn is 0.8. If the ball is white, find the probability that the second urn was selected.  </SPAN>\n" );
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document.write( "P(first urn selected and ball is white) = (0.8)(4/10) = (0.8)(0.4) = 0.32<br><BR>\n" );
document.write( "P(second urn selected and ball is white) - (0.2)(6/10) =(0.2)(0.6) = 0.12<br><BR>\n" );
document.write( "P(ball is white) = 0.32+0.12 = 0.44<br><BR>\n" );
document.write( "P(ball is white, given that it came from second urn) = 0.12/0.44 = 12/44 = 3/11<br><BR>\n" );
document.write( "ANSWER: 3/11<br><BR>\n" );
document.write( "Convert to decimal or percentage if required....<br><BR>\n" );
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