document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=144043>Question 144043</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You toss 3 coins. What is the probability that you get exactly 2 heads, given that you get at least one head? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #104837 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=104837\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You toss 3 coins. What is the probability that you get exactly 2 heads, given that you get at least one head?<BR>\n" );
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document.write( "Formula: P(A|B) =[P(A and B)] / P(B)<BR>\n" );
document.write( "P(2 heads on 3 tosses | get at least one head)<BR>\n" );
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document.write( "P(at least one head) = 1-P(no heads in three) = 1-1/8 = 7/8<BR>\n" );
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document.write( "P(2 heads AND at least one head) = P(3 heads) = 1/8<BR>\n" );
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document.write( "So< P(2 heads on 3 toses | get at least one head) = [1/8]/[7/8]  1/7<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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