document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1106683>Question 1106683</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A technician is launching fireworks near the end of a show. Of the remaining thirteen fireworks, seven are blue and six are red. If she launches six of them in a random order, what is the probability that exactly two of them are blue ones?\r<BR>\n" );
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document.write( "Hi, I have attempted this question multiple times and while I get the total number of ways she can select 6 out of 13 (1716)\r<BR>\n" );
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document.write( "My answer does not match the textbook's for the number of ways she can get 2 out of 6. The correct answer is supposed to be 105/572 but I get 75/572 \r<BR>\n" );
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document.write( "I would really appreciate the help, thanks so much  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #721679 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=721679\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Note that we would be in a much better position to tell you why you are getting the wrong answer if you SHOWED us how you got it....<br><BR>\n" );
document.write( "You want 2 of the 6 she chooses to be blue, which means 4 are red.  There are 7 blue and 6 red remaining.<br><BR>\n" );
document.write( "She is choosing 6 of the remaining 13 fireworks; the number of ways she can do that is \"13 choose 6\".<br><BR>\n" );
document.write( "You want the probability that of those 6, 2 are blue and 4 are red.  So she needs to choose 2 of the 7 remaining blue fireworks (7 choose 2) and 4 of the remaining 6 red fireworks (6 choose 4).<br><BR>\n" );
document.write( "So the calculation should be straightforward:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28C%287%2C2%29%2AC%286%2C4%29%29%2FC%2813%2C6%29 ALIGN=MIDDLE  ALT=\"%28C%287%2C2%29%2AC%286%2C4%29%29%2FC%2813%2C6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2821%2A15%29%2F1716+=+%287%2A15%29%2F572+=+105%2F572 ALIGN=MIDDLE  ALT=\"%2821%2A15%29%2F1716+=+%287%2A15%29%2F572+=+105%2F572\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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