document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=689265>Question 689265</A>: <I><SPAN STYLE=\"word-break: break-all;\"> there are 6 MC questions in a short quiz and 5 options are given for each question. 2 marks are awarded for a correct answer and 1 mark is deducted for a wrong answer. If a student answers the questions by guessing, find the probability that\r<BR>\n" );
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document.write( "a. his total scoreis is negative;<BR>\n" );
document.write( "b. his total scoreis is zero;<BR>\n" );
document.write( "c. his total scoreis is postive. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #425883 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><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=425883\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If the student simply guesses on each question, he has a 20% chance of guessing correctly (1 chance in 5) and and 80% chance of guessing incorrectly (4 chances in 5).\r<BR>\n" );
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document.write( "So what are the points at those odds?<BR>\n" );
document.write( "The student has 20% at 2 points. Or 0.2*2 = 0.4 per question<BR>\n" );
document.write( "The student has 80 at -1 points. Or 0.8 * (-1) = -0.8 per question\r<BR>\n" );
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document.write( "Net, pure guessing is a losing deal here. \r<BR>\n" );
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document.write( "If the student could correctly eliminate one potential answer before guessing, he breaks even. If he can eliminate 2 potential answers before guessing, he comes out ahead. \r<BR>\n" );
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document.write( "FYI ... SAT is scored with negative points for an incorrect answer. For SAT hints on guessing see <BR>\n" );
document.write( "http://www.math.com/students/kaplan/sat_intro/guess2.htm\r<BR>\n" );
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document.write( "Answer A </SPAN>\n" );
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