document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=124182>Question 124182</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I thought I understood the material presented in class but need assistance in completing/understanding problem:\r<BR>\n" );
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document.write( "A student is to use random guessing on a multiple-choice test.  Out of five choices, there is only one correct answer for each question.  Assume that you will observe the first three guesses by the student.\r<BR>\n" );
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document.write( "a. Find the sample space. <BR>\n" );
document.write( "b. Construct a probability distribution for the number of questions answered correctly, x.<BR>\n" );
document.write( "c. Draw the probability histogram <BR>\n" );
document.write( "d. find the standard deviation of the number of questions answered correctly<BR>\n" );
document.write( "e. find the expected value of the number of questions answered correctly<BR>\n" );
document.write( "f. Give one-, two-, and three sigma interval\r<BR>\n" );
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document.write( "Appreciate your assistance in getting me started and understanding this better.  This is a problem generated by the instructor and really can't find a good reference in the book we are using.<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 #91109 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=91109\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A student is to use random guessing on a multiple-choice test. Out of five choices, there is only one correct answer for each question. Assume that you will observe the first three guesses by the student. <BR>\n" );
document.write( "a. Find the sample space.<BR>\n" );
document.write( "ttt,ttf,tft,ftt,tff,ftf,fft,fff<BR>\n" );
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document.write( "b. Construct a probability distribution for the number of questions answered correctly, x.<BR>\n" );
document.write( "P(x=3) = 1/8 ; P(x=2) = 3/8 ; P(x=1) = 3/8 ; P(x=0) = 1/8<BR>\n" );
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document.write( "c. Draw the probability histogram <BR>\n" );
document.write( "I'll leave that to you.<BR>\n" );
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document.write( "d. find the standard deviation of the number of questions answered correctly<BR>\n" );
document.write( "I'll leave that to you.<BR>\n" );
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document.write( "e. find the expected value of the number of questions answered correctly<BR>\n" );
document.write( "E(x)= 0*(1/8)+1(3/8)+2(3/8)+3(1/8) =  3/2<BR>\n" );
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document.write( "f. Give one-, two-, and three sigma interval<BR>\n" );
document.write( " DISABLED_event_one=  (3/2)+sigma= <BR>\n" );
document.write( "two = (3/2)+2*sigma=<BR>\n" );
document.write( "three = (3/2)+3*sigma=  <BR>\n" );
document.write( "===========================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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