document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1033544>Question 1033544</A>: <I><SPAN STYLE=\"word-break: break-all;\"> . A test consists of 10 multiple choice questions with five choices for each question. As an experiment,you GUESS on each and every answer without even reading the questions.<BR>\n" );
document.write( "What is the probability of getting exactly 7 questions correct on this test?\r<BR>\n" );
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document.write( "Someone please help me, I cant wrap my head around this question. How do I go about finding \"P\"<BR>\n" );
document.write( "I know n=10 r=7 p=? q=1-p\r<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 #648201 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=648201\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> p=0.2; q, or 1-p=0.8<BR>\n" );
document.write( "exactly 7 questions right<BR>\n" );
document.write( "10C7(0.2)^7(0.8)^3.<BR>\n" );
document.write( "The 10C7 is the number of ways 7 questions can be answered correctly out of 10.  It is 10!/7!3!=120<BR>\n" );
document.write( "120*0.2^7*0.8^3=0.0008<BR>\n" );
document.write( "For any number of questions right, use 0.2, which is the likelihood of guessing right with 5 choices, 1/5, and raise it to the number you want.  Then use the complement of 0.2, or 0.8, and raise it to the number you want.  The exponents must add up to the number of trials, in this instance 10. </SPAN>\n" );
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