document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=438102>Question 438102</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A tire manufacturer believes the tread life of snow tires has a normal distribution with mean of 32000 and standard deviation of 7000 miles.If the dealer is willing to give refunds to no more than 1 in 50 tires sold ,what mileage can he guarantee each tire to last? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #303024 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=303024\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A tire manufacturer believes the tread life of snow tires has a normal distribution with mean of 32000 and standard deviation of 7000 miles.If the dealer is willing to give refunds to no more than 1 in 50 tires sold ,what mileage can he guarantee each tire to last?<BR>\n" );
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document.write( "1/50 is 2%<BR>\n" );
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document.write( "Find the z-value with a left-tail of 98%<BR>\n" );
document.write( "invNorm(0.98) = 2.0537<BR>\n" );
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document.write( "solve for the corresponding x-value:<BR>\n" );
document.write( "x = zs + u<BR>\n" );
document.write( "x = 2.04537*7000+32000<BR>\n" );
document.write( "x = 46376.24 miles (the mileage he can guarantee)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "============<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );