document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=173091>Question 173091</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The inside diameter of metal washers produced by a company are normally distributed with a mean of 0.5 inches and a standard deviation of 0.01 inches. Of all washers produced, 0.8% of the washers are rejected because they are to small for a bolt used to test them. What is the diameter of the bolt used for the test?\r<BR>\n" );
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document.write( "I have tried almost every formula and I cannot seem to get this one at all, please help! Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #127964 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=127964\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The inside diameter of metal washers produced by a company are normally distributed with a mean of 0.5 inches and a standard deviation of 0.01 inches. Of all washers produced, 0.8% of the washers are rejected because they are to small for a bolt used to test them. What is the diameter of the bolt used for the test? <BR>\n" );
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document.write( "Draw a normal curve and put 0.5\" in the middle.<BR>\n" );
document.write( "Mark a left tail that has 0.8% of the population in it.<BR>\n" );
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document.write( "0.8% = 0.8/100 = 0.008<BR>\n" );
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document.write( "Find the z-value below which 0.8% of the population lies.<BR>\n" );
document.write( "That z-value is -2.408916...<BR>\n" );
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document.write( "Now find the x-value (raw score) that corresponds to that z-value using:<BR>\n" );
document.write( "z = (x-u)/sigma<BR>\n" );
document.write( "-2.408916 = (x-0.5)/0.01<BR>\n" );
document.write( "x-0.5 = 0.01*-2.408916 = -0.024089<BR>\n" );
document.write( "x = 0.475910...<BR>\n" );
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document.write( "The washer must have had a diameter < 0.475910 inches<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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