document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=425908>Question 425908</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a couple has three children, what is the probability that they have at least one boy. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #296394 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=296394\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the probability of at least a boy is 1 minus the probability of no boys.\r<BR>\n" );
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document.write( "the probability that each child will be a boy is 1/2.<BR>\n" );
document.write( "the probability that each child will be a girl is 1/2.\r<BR>\n" );
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document.write( "the probability of no boys = 1/2 * 1/2 * 1/2 = 1/8\r<BR>\n" );
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document.write( "the probability of at least 1 boy is 1 minus the probability of no boys.\r<BR>\n" );
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document.write( "this equals 1 - 1/8 = 7/8\r<BR>\n" );
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document.write( "the breakdown of the possibilities is shown below:\r<BR>\n" );
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document.write( "probability of 0 boys = 1/8<BR>\n" );
document.write( "probability of 1 boy = 3 * 1/8 = 3/8<BR>\n" );
document.write( "probability of 2 boys = 3 * 1/8 = 3/8<BR>\n" );
document.write( "probability of 3 boys = 1/8\r<BR>\n" );
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document.write( "total probability should be equal to 1.\r<BR>\n" );
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document.write( "1/8 + 3/8 + 3/8 + 1/8 = 1\r<BR>\n" );
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document.write( "you can see from this that the probability of at least 1 boy is equal to the probability of 1 or 2 or 3 boys which equals 3/8 + 3/8 + 1/8 = 7/8\r<BR>\n" );
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document.write( "this is the same as 1 minus the probability of 0 boys.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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