document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=75989>Question 75989</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Juan Salvador just completed a study of the life expectancy of 100 light bulbs and discovered that the mean time that they lasted before burning out was 1,900 hours. If the standard deviation was 150 hours, the empirical rule allows Juan to conclude that approximately 68 of the bulbs burned out between _________ and _________ hours.\r<BR>\n" );
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document.write( "         a.   1,750, 2,050\r<BR>\n" );
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document.write( "         b.   1,800, 1,900.\r<BR>\n" );
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document.write( "         c.   1,600, 2,200.\r<BR>\n" );
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document.write( "         d.   1,450, 2,350.\r<BR>\n" );
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document.write( "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 #54583 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=54583\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Juan Salvador just completed a study of the life expectancy of 100 light bulbs and discovered that the mean time that they lasted before burning out was 1,900 hours. If the standard deviation was 150 hours, the empirical rule allows Juan to conclude that approximately 68 of the bulbs burned out between _________ and _________ hours. <BR>\n" );
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document.write( "68% of the population is within one standard deviation of the mean; one<BR>\n" );
document.write( "to the left and one to the right.<BR>\n" );
document.write( "One standard deviation to the left is 1900-150=1750 hrs<BR>\n" );
document.write( "One standard deviation to the right is 1900+150=2050 hrs\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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