document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=435144>Question 435144</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me with these probability questions. The help I received early was not correct.\r<BR>\n" );
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document.write( "A test consists of 10 true-or-false questions. An answer is randomly chosen for each question.<BR>\n" );
document.write( "7. (1 point) What is the probability of answering exactly 4 questions correctly? Answer in fraction.<BR>\n" );
document.write( "8. (1 point) What is the probability of answering at least 2 questions correctly? Answer in fraction. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #301287 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=301287\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A test consists of 10 true-or-false questions. An answer is randomly chosen for each question.<BR>\n" );
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document.write( "Binomial Problem with n = 10 and p = 1/2<BR>\n" );
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document.write( "7. (1 point) What is the probability of answering exactly 4 questions correctly? Answer in fraction.<BR>\n" );
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document.write( "P(x = 4) = 10C4*(1/2)^4*(1/2)^6 = 210/1024<BR>\n" );
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document.write( "8. (1 point) What is the probability of answering at least 2 questions correctly? Answer in fraction.<BR>\n" );
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document.write( "P(x>= 2) = 1- P(0<= x <=1)<BR>\n" );
document.write( "= 1 - [P(x=0) + P(x=1)]<BR>\n" );
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document.write( "= 1- [10C0(1/2)^10 + 10C1(1/2)^10]<BR>\n" );
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document.write( "= 1 -[(1+10)/1024]<BR>\n" );
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document.write( "= 1013/1024<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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