document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1019725>Question 1019725</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A pair if dice is rolled four times. Find the probability of rolling an even total exactly once. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #635793 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=635793\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the probability of getting an even number total on any one roll of the pair of dice is .5\r<BR>\n" );
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document.write( "the probability of not getting an even number total on any one roll of the pair of dice is therefore also equal to .5.\r<BR>\n" );
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document.write( "p = probability of success = .5<BR>\n" );
document.write( "q = probability of failure = 1 - p = .5\r<BR>\n" );
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document.write( "the formula for binomial probability is:\r<BR>\n" );
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document.write( "p(x) = p^x * q^(n-x) * c(n,x)\r<BR>\n" );
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document.write( "in your problem:\r<BR>\n" );
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document.write( "x = 1<BR>\n" );
document.write( "n = 4<BR>\n" );
document.write( "p = .5<BR>\n" );
document.write( "q = .5<BR>\n" );
document.write( "n-x = 4-1 = 3\r<BR>\n" );
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document.write( "p(x) = p^x * q^(n-x) * c(n,x) becomes:\r<BR>\n" );
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document.write( "p(1) = .5^1 * .5^3 * c(4,1)\r<BR>\n" );
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document.write( "c(4,1) = 4! / (1! * 3!) = (4*3!) / (3!) = 4\r<BR>\n" );
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document.write( "this becomes:<BR>\n" );
document.write( "p(1) = .5^1 * .5^3 * 4 which becomes:<BR>\n" );
document.write( "p(1) = .5 * .125 * 4 which becomes:<BR>\n" );
document.write( "p(1) = .25\r<BR>\n" );
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document.write( "the probability of rolling an even total exactly 1 time is equal to .25\r<BR>\n" );
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document.write( " </SPAN>\n" );
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