document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1007965>Question 1007965</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone PLEASE HELP!!!\r<BR>\n" );
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document.write( "Suppose we want to determine the (binomial) probability (p) of getting 5 heads in 15 flips of a 2-sided coin.  Using the Binomial table in the appendix of the text, what values of n, x, and p would we use to look up this probability, and what would be the probability? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #623806 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=623806\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> p(x) = c(n,x) * p^x * q^(n-x)\r<BR>\n" );
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document.write( "x = 5<BR>\n" );
document.write( "n = 15<BR>\n" );
document.write( "p = .5<BR>\n" );
document.write( "q = .5\r<BR>\n" );
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document.write( "formula becomes:\r<BR>\n" );
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document.write( "p(5) = c(15,5) * .5^5 * .5^10\r<BR>\n" );
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document.write( "solve for p(5) to get:\r<BR>\n" );
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document.write( "p(5) = .0916442871\r<BR>\n" );
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document.write( "c(15,5) is the combination formula for the number of ways to select 5 things out of 15 where order doesn't matter.\r<BR>\n" );
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document.write( "the general formula is c(n,x) = n! / (x! * (n-x)!)\r<BR>\n" );
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document.write( "when n = 15 and x = 5, c(n,x) becomes:\r<BR>\n" );
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document.write( "c(15,5) = 15! / (5! * 10!) = (15*14*13*12*11*10!) / (5! * 10!)\r<BR>\n" );
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document.write( "this becomes:\r<BR>\n" );
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document.write( "c(15,5) = (15*14*13*12*11) / (5*4*3*2*1) which becomes (21*13*11 which is equal to 3003.\r<BR>\n" );
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document.write( "c(15,5) * p^x * q^(n-x) becomes 3003 * .5^5 * .5^10 which becomes 3003 * .5^15 which becomes .0916442871\r<BR>\n" );
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document.write( "that's the probability of getting exactly 5 heads out of 15 tosses.\r<BR>\n" );
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document.write( "the value of n is 15.<BR>\n" );
document.write( "the value of x is 5<BR>\n" );
document.write( "the value of p is .5\r<BR>\n" );
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document.write( "the full probability table for this problem is shown below:\r<BR>\n" );
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document.write( "the total probability is equal to 1 as it should be.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2015/120401.jpg\" alt=\"$$$\" </>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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