document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=564989>Question 564989</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Veronica has observed 200 bicycles at an intersection and found that 80% did not make a complete stop. Veronica tells you that the margin of error was 4%. What was the confidence level of the study? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #365696 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=365696\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Veronica has observed 200 bicycles at an intersection and found that 80% did not make a complete stop. Veronica tells you that the margin of error was 4%. What was the confidence level of the study?<BR>\n" );
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document.write( "ME = z*sqrt(pq/n)<BR>\n" );
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document.write( "0.04 = z*sqrt[0.8*0.2/200)<BR>\n" );
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document.write( "0.04 = z*0.0283<BR>\n" );
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document.write( "z = 1.4142<BR>\n" );
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document.write( "normalcdf(1.4142,100) = 0.0786<BR>\n" );
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document.write( "Confidence level = 1 - 2*0.0786 = 84.27%<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
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