document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=246478>Question 246478</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ok so: There are 15 questions on a multiple-choice exam and five possible answers to each question. <BR>\n" );
document.write( "(a) In how many ways can the exam be answered? (I put 5^15 is that correct? Since the questions are all distinct, and any number of questions could be answered for example a out of a,b,c,d,e.)<BR>\n" );
document.write( "(b) In how many ways can the exam be answered with exactly 8 answers correct? (Is this 5^7?)\r<BR>\n" );
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document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #181783 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=181783\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a-<BR>\n" );
document.write( "There are 15 questions.<BR>\n" );
document.write( "Each question has 5 possible answers.<BR>\n" );
document.write( "5^15 is not correct.<BR>\n" );
document.write( "Why are you trying to raise 5 to a power?<BR>\n" );
document.write( "Think about what that does. <BR>\n" );
document.write( "let's say there are only two questions with 5 possible answers<BR>\n" );
document.write( "so with your method there would be 5*5 possible answers=25<BR>\n" );
document.write( "but we know <BR>\n" );
document.write( "the first question has 5 possible answers<BR>\n" );
document.write( "the second questions has five possible answers\r<BR>\n" );
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document.write( "lets make it only three questions<BR>\n" );
document.write( "the first question has 5 possible answers<BR>\n" );
document.write( "the second questions has five possible answers<BR>\n" );
document.write( "the third question has five possible answers<BR>\n" );
document.write( "This should give you a hint to how many answers 15 questions might have.<BR>\n" );
document.write( "b-<BR>\n" );
document.write( "so what has happened?<BR>\n" );
document.write( "8 questions have been reduced to only one possible answer -the correct one.<BR>\n" );
document.write( "that leaves 7 with 5 possible answers<BR>\n" );
document.write( "so work out how many possible answers there are for those 7 and add 8 to it for the 8 correct answers\r<BR>\n" );
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document.write( " </SPAN>\n" );
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