document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=401943>Question 401943</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need assistance with the following statistics:\r<BR>\n" );
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document.write( "A literature professor decides to give a 20 question true-false quiz.  She wants to choose the passing grade such that the probability of passing a student who guesses on every question is less than .10.  What score should be set as the lowest passing grade?\r<BR>\n" );
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document.write( "Thanks,<BR>\n" );
document.write( "Glenda Witherspoon </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #284441 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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/cgi-bin/show-face.mpl?user=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=284441\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let X = r.v. representing the number of correct answers.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29%5E20%2A%28sum%2820Cx%2C+x+=+0%2C+6%29%29+=+0.05766 ALIGN=MIDDLE  ALT=\"%281%2F2%29%5E20%2A%28sum%2820Cx%2C+x+=+0%2C+6%29%29+=+0.05766\"   DISABLED_style= \"max-width:90%; height:auto;\" >, to 5 decimal places.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29%5E20%2A%28sum%2820Cx%2C+x+=+0%2C+7%29%29+=+0.13159 ALIGN=MIDDLE  ALT=\"%281%2F2%29%5E20%2A%28sum%2820Cx%2C+x+=+0%2C+7%29%29+=+0.13159\"   DISABLED_style= \"max-width:90%; height:auto;\" >, to 5 decimal places.\r<BR>\n" );
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document.write( "Therefore the lowest passing grade is a 7. </SPAN>\n" );
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