document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=759800>Question 759800</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a box contains 12 balls of which 4 are green and 8 are red. if 7 balls are drawn from the box at random, one by one with replacement, find the probability that exactily 3 balls drawn are green.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #462227 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20056)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=462227\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a box contains 12 balls of which 4 are green and 8 are red. if 7 balls are drawn from the box at random, one by one with replacement, find the probability that exactily 3 balls drawn are green. <BR>\n" );
document.write( "<br><br><font face=\"times new roman\" size=4><BR>\n" );
document.write( "First we will find the probability of drawing the 7 in this particular order:<BR>\n" );
document.write( "GGGRRRR, where G = drawing a green ball and R = drawing a red ball.<BR>\n" );
document.write( "That is,<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%284%2F12%29%284%2F12%29%284%2F12%29%288%2F12%29%288%2F12%29%288%2F12%29%288%2F12%29 ALIGN=MIDDLE  ALT=\"%284%2F12%29%284%2F12%29%284%2F12%29%288%2F12%29%288%2F12%29%288%2F12%29%288%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%284%2F12%29%5E3%288%2F12%29%5E4 ALIGN=MIDDLE  ALT=\"%284%2F12%29%5E3%288%2F12%29%5E4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F3%29%5E3%282%2F3%29%5E4 ALIGN=MIDDLE  ALT=\"%281%2F3%29%5E3%282%2F3%29%5E4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F3%5E3%29%282%5E4%2F3%5E4%29 ALIGN=MIDDLE  ALT=\"%281%2F3%5E3%29%282%5E4%2F3%5E4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%5E4%2F3%5E7 ALIGN=MIDDLE  ALT=\"2%5E4%2F3%5E7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16%2F2187 ALIGN=MIDDLE  ALT=\"16%2F2187\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "But they do not have to be chosen in the particular order GGGBBBB.<BR>\n" );
document.write( "For instance, the order BBGBGBG or GBGBGBB would do just as well. <BR>\n" );
document.write( "So we must multiply the probability of the particular order GGGBBBB <BR>\n" );
document.write( "by the number of all possible orders. That is the number of ways to<BR>\n" );
document.write( "choose 3 of the 7 positions to draw the 3 green balls in or <BR>\n" );
document.write( "C(7,3) = 35. (The other 4 positions will of course be red balls).<br><BR>\n" );
document.write( "So the answer is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=35 ALIGN=MIDDLE  ALT=\"35\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22%2A%22%22 ALIGN=MIDDLE  ALT=\"%22%22%2A%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16%2F2187 ALIGN=MIDDLE  ALT=\"16%2F2187\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=560%2F2187 ALIGN=MIDDLE  ALT=\"560%2F2187\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Edwin</pre> </SPAN>\n" );
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