document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=449390>Question 449390</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A True-False test has 20 questions with each having 2 possible answers with one correct. Assume a student randomly guesses the answer to every question. (2.5 points each)\r<BR>\n" );
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document.write( "a. What is the probability of getting exactly 9 correct answers?\r<BR>\n" );
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document.write( "b. What is the probability of getting fewer than 6 correct answers?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #309145 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=309145\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A True-False test has 20 questions with each having 2 possible answers with one correct. Assume a student randomly guesses the answer to every question. (2.5 points each)<BR>\n" );
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document.write( "Binomial Problem with n= 20 and p = 1/2<BR>\n" );
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document.write( "a. What is the probability of getting exactly 9 correct answers?<BR>\n" );
document.write( "P(x = 9) = 20C9(1/2)^20 = 167969/2^20 = 0.1602<BR>\n" );
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document.write( "b. What is the probability of getting fewer than 6 correct answers?<BR>\n" );
document.write( "P(0<= x <=5) = binomcdf(20,1/2,5) = 0.0207<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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