document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=865077>Question 865077</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A hospital emergency room has collected a sample of n = 40 to estimate the mean number of visits per day. It has found the standard deviation is 32. Using a 90 percent confidence level, what is its margin of error? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #521494 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=521494\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Using <a  rel=nofollow HREF=\"http://3.bp.blogspot.com/_5u1UHojRiJk/TEdJJc6of2I/AAAAAAAAAIE/Ai0MW5VgIhg/s1600/t-table.jpg\">this table</a>, the critical value for the 90% confidence level is 1.645 (note: look in the row that starts with <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=infinity ALIGN=MIDDLE  ALT=\"infinity\"   DISABLED_style= \"max-width:90%; height:auto;\" > and look for the value above 90%)\r<BR>\n" );
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document.write( "So z = 1.645\r<BR>\n" );
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document.write( "Given Information:\r<BR>\n" );
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document.write( "n = 40<BR>\n" );
document.write( "s = 32\r<BR>\n" );
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document.write( "Margin Of Error (ME)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ME+=+z%2A%28s%2Fsqrt%28n%29%29 ALIGN=MIDDLE  ALT=\"ME+=+z%2A%28s%2Fsqrt%28n%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ME+=+1.645%2A%2832%2Fsqrt%2840%29%29 ALIGN=MIDDLE  ALT=\"ME+=+1.645%2A%2832%2Fsqrt%2840%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ME+=+8.32311480156 ALIGN=MIDDLE  ALT=\"ME+=+8.32311480156\"   DISABLED_style= \"max-width:90%; height:auto;\" > Using a <a  rel=nofollow HREF=\"https://www.google.com/search?q=1.645*(32/sqrt(40))\">calculator</a> here.\r<BR>\n" );
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document.write( "So the margin of error is approximately <font color=\"red\">8.32311480156</font>\r<BR>\n" );
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document.write( "Don't forget to round that if needed. According to the instructions posted that I see, there are no rounding instructions, but they may want you to round. </SPAN>\n" );
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