document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=280800>Question 280800</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The length of steel rods cut by a machine is normally distributed with mean 13.8 cm. It is found that 1.5% of all rods are less than 13.2 cm long. Find the standard deviation of rod lengths produced by this machine.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #204053 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=204053\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The length of steel rods cut by a machine is normally distributed with mean 13.8 cm. It is found that 1.5% of all rods are less than 13.2 cm long. Find the standard deviation of rod lengths produced by this machine. <BR>\n" );
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document.write( "Find the z-score with left tail = 0.015<BR>\n" );
document.write( "invNorm(0.015) = -2.1701<BR>\n" );
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document.write( "Use the form: x = zs+u to find \"s\":<BR>\n" );
document.write( "13.2 = -2.1701s + 13.8<BR>\n" );
document.write( "-2.1701s = -0.6<BR>\n" );
document.write( "s = standard deviation = 0.2765<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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