document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=285518>Question 285518</A>: <I><SPAN STYLE=\"word-break: break-all;\"> suppose you are writing a multiple choice exam in which each answer has 5 choices. you decide to use in which you place 5 balls in a box (marked A,B,C,D,E). you randomly select 1 ball for each question and replace it, the marking on the ball determines your answer to the question. If there are 10 questions, <BR>\n" );
document.write( "1. what is the probability of getting 5 questions correct?<BR>\n" );
document.write( "2. getting at least 3 questions correct?<BR>\n" );
document.write( "3. what is the expected number of correct answers?<BR>\n" );
document.write( "4. what is the standard deviation? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #207033 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=207033\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> suppose you are writing a multiple choice exam in which each answer has 5 choices. you decide to use in which you place 5 balls in a box (marked A,B,C,D,E). you randomly select 1 ball for each question and replace it, the marking on the ball determines your answer to the question. If there are 10 questions,<BR>\n" );
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document.write( "Binomial Problem with n = 10 ; p = 1/5 <BR>\n" );
document.write( "1. what is the probability of getting 5 questions correct?: <BR>\n" );
document.write( "Ans: binompdf(10,1/5,5) =<BR>\n" );
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document.write( "2. getting at least 3 questions correct?:<BR>\n" );
document.write( "Ans: 1-binomcdf(10,1/5,2) = <BR>\n" );
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document.write( "3. what is the expected number of correct answers?<BR>\n" );
document.write( "ans: mean = np = 10(1/5) = 2<BR>\n" );
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document.write( "4. what is the standard deviation?<BR>\n" );
document.write( " Ans: std = sqrt(npq) = sqrt(2*4/5) = sqrt(8/5) = 1.2649\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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