document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=669059>Question 669059</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An instructor gives his class a set of 19 problems with the information that the next quiz will consist of a random selection of 9 of them. If a student has figured out how to do 12 of the problems, what is the probability the he or she will answer correctly <BR>\n" );
document.write( "(a) all 9 problems? <BR>\n" );
document.write( "(b) at least 8 problems?\r<BR>\n" );
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document.write( "Thank you for your time. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #416042 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=416042\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An instructor gives his class a set of 19 problems with the information that the next quiz will consist of a random selection of 9 of them. If a student has figured out how to do 12 of the problems, what is the probability the he or she will answer correctly<BR>\n" );
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document.write( "Binomial Problem with n= 19 ; p(correct) = 12/19 ; p(wrong) = 7/19<BR>\n" );
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document.write( "(a) all 9 problems?<BR>\n" );
document.write( "P(x = 9) = 19C9(12/19)^9*(7/19)^10 = binompdf(19,12/19,9) = 0.0681<BR>\n" );
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document.write( "(b) at least 8 problems?<BR>\n" );
document.write( "P(8<= x <=19) = 1 - binomcdf(19,12/19,7) = 0.9822<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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