document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=302971>Question 302971</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Truck tire life is normally distributed with a mean of 60,000 miles and a standard deviation of 4,000 miles.<BR>\n" );
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document.write( "- You bought 4 tires. What is the probability that the average mileage of the 4 tires exceeds 66,000 miles?<BR>\n" );
document.write( "a.) 0.0013<BR>\n" );
document.write( "b.) 0.9987<BR>\n" );
document.write( "c.) 0.4987<BR>\n" );
document.write( "d.) 0.9544\r<BR>\n" );
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document.write( "- What is the probability that 1 tire will last 72,000 miles or more?<BR>\n" );
document.write( "a.) 0.0013<BR>\n" );
document.write( "b.) 0.9987<BR>\n" );
document.write( "c.) 0.4987<BR>\n" );
document.write( "d.) 0.9544\r<BR>\n" );
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document.write( "Thank you for your help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #217172 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=217172\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Truck tire life is normally distributed with a mean of 60,000 miles and a standard deviation of 4,000 miles.\r<BR>\n" );
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document.write( "- You bought 4 tires. What is the probability that the average mileage of the 4 tires exceeds 66,000 miles?<BR>\n" );
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document.write( "z(66,000) = (66000-60000)/[4000/sqrt(4)] = 6000/2000 = 3<BR>\n" );
document.write( "P(x > 66000) = P(z> 3) = 0.0013\r<BR>\n" );
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document.write( "a.) 0.0013<BR>\n" );
document.write( "b.) 0.9987<BR>\n" );
document.write( "c.) 0.4987<BR>\n" );
document.write( "d.) 0.9544<BR>\n" );
document.write( "---------------------------------- <BR>\n" );
document.write( "- What is the probability that 1 tire will last 72,000 miles or more?<BR>\n" );
document.write( "z(72000) = (72000-60000)/4000 = 12000/4000 = 3<BR>\n" );
document.write( "P(z> 72000)= P(z > 3) = 0.0013<BR>\n" );
document.write( "---<BR>\n" );
document.write( "a.) 0.0013<BR>\n" );
document.write( "b.) 0.9987<BR>\n" );
document.write( "c.) 0.4987<BR>\n" );
document.write( "d.) 0.9544 <BR>\n" );
document.write( "Thank you for your help!<BR>\n" );
document.write( "==================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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