document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=438334>Question 438334</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me.....I am having a hard time solving this problem.\r<BR>\n" );
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document.write( "The operating life of a Sports Master fishing reel is normally distributed with mean 48 months and standard deviation 6 months.  The manufacturer will replace any Sports Master reel that malfunctions during the guarantee period.<BR>\n" );
document.write( "   a) if the guarantee period is 45 months, what percent of the reels will Sports Master have to replace? compute.\r<BR>\n" );
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document.write( "   b) How long should the guarantee period be if the manufacturer does not want to replace more than 5% of the reels? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #303157 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=303157\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The operating life of a Sports Master fishing reel is normally distributed with mean 48 months and standard deviation 6 months. The manufacturer will replace any Sports Master reel that malfunctions during the guarantee period.<BR>\n" );
document.write( "a) if the guarantee period is 45 months, what percent of the reels will Sports Master have to replace? compute.<BR>\n" );
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document.write( "z(45) = (45-48)/6 = -1/2<BR>\n" );
document.write( "% of sales covered by the warranty = P(z < -1/2) = 0.3085 = 30.85%<BR>\n" );
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document.write( "b) How long should the guarantee period be if the manufacturer does not want to replace more than 5% of the reels?<BR>\n" );
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document.write( "Find the z-value with a left tail of 5%<BR>\n" );
document.write( "invNorm(0.05) = -1.645<BR>\n" );
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document.write( "Find the corresponding x-value:<BR>\n" );
document.write( "x = zs+u<BR>\n" );
document.write( "x = -1.645*6+48 = 38.13 months<BR>\n" );
document.write( "Make the guarantee period 39 months<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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