document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=159742>Question 159742</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The directions say,\"In exercise 2, consider a 10-question true/false test.\" The question is, 'How many ways are there to score exactly 80%? That is, how many ways are there to get exactly 2 questions wrong? Explain why choosing which questions you will get wrong determines all your answers.' </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #117773 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=117773\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The directions say,\"In exercise 2, consider a 10-question true/false test.\" The question is, 'How many ways are there to score exactly 80%? That is, how many ways are there to get exactly 2 questions wrong? Explain why choosing which questions you will get wrong determines all your answers.<BR>\n" );
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document.write( "True/False questions are binomial because there are only two possible answers.<BR>\n" );
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document.write( "2 wrong out of 10 is the same as 8 right out of 10<BR>\n" );
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document.write( "Ans: # of ways to select 2 from 10 is 10C2 = [10*9]/[1*2] = 45<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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