document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=479673>Question 479673</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The lifetime of ZZZ batteries is normally distributed with a mean of 270 hours and a standard deviation of 10 hours. What number of hours would represent the 40th percentile in this distribution?  Please help me with this I do t understand it & how to show my work. Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #328624 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=328624\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The lifetime of ZZZ batteries is normally distributed with a mean of 270 hours and a standard deviation of 10 hours. What number of hours would represent the 40th percentile in this distribution? <BR>\n" );
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document.write( "Find the z-value with a left-tail of 40%<BR>\n" );
document.write( "invNorm(0.40) = -0.2533<BR>\n" );
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document.write( "find the correspondign hour value using x = zs+u<BR>\n" );
document.write( "x = -0.2533*10+ 270 = 267.47 hrs.<BR>\n" );
document.write( "Round up to 267 hrs<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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