document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1169237>Question 1169237</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Sales A manufacturer makes two models of an item: model I, which accounts for 80% of unit sales, and model II, which accounts for 20% of unit sales. Because of defects, the manufacturer has to replace (or exchange) 10% of its model I and 18% of its model II. If a model is selected at random, find the probability that it will be defective </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #793881 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=793881\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the defect rate on m1 = .1<BR>\n" );
document.write( "the defect rate on m2 = .18<BR>\n" );
document.write( "m1 = model 1<BR>\n" );
document.write( "m2 = model 2<BR>\n" );
document.write( "t = total sales of m1 and m2<BR>\n" );
document.write( "m1 = .8 * t<BR>\n" );
document.write( "m2 = .2 * t<BR>\n" );
document.write( "defective m1 = .1 * m1<BR>\n" );
document.write( "defective m2 = .18 * m2\r<BR>\n" );
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document.write( "total defective = .1 * m1 + .18 * m2<BR>\n" );
document.write( "since m1 = .8 * t and m2 = .2 * t, then:<BR>\n" );
document.write( "total defective = .1 * .8 * t + .18 * .2 * t<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "total defective = .116 * t = 11.6%\r<BR>\n" );
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document.write( "to see how this works, assume they sold a total of 1000 cars.\r<BR>\n" );
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document.write( "m1 was 80% of them = 800<BR>\n" );
document.write( "m2 was 20% of them = 200\r<BR>\n" );
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document.write( "10% of m1 was defective = 10% of 800 = 80<BR>\n" );
document.write( "18% of m2 was defective = 18% of 200 = 36\r<BR>\n" );
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document.write( "total defective = 116<BR>\n" );
document.write( "percent defective of total = 116/1000 = .116 * 100 = 11.6%.\r<BR>\n" );
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document.write( "divide percent by 100 to get rate.<BR>\n" );
document.write( "multiply rate by 100 to get percent.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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