document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1087907>Question 1087907</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the probability of this trial, x = 8, n = 11, p = 0.9, where x is successes in n trials.<BR>\n" );
document.write( "a. 9%<BR>\n" );
document.write( "b. 7%<BR>\n" );
document.write( "c. 19% </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #702190 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=702190\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=\"black\" face=\"times\" size=\"3\">We have n = 11 as the sample size, p = 0.9 as the probability of success, and k = 8 as the number of successes (I'm using k instead of x)\r<BR>\n" );
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document.write( "Plug in n = 11 and k = 8 into the combination formula below\r<BR>\n" );
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document.write( "n C k = (n!)/(k!*(n-k)!)\r<BR>\n" );
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document.write( "11 C 8 = (11!)/(8!*(11-8)!)\r<BR>\n" );
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document.write( "11 C 8 = (11!)/(8!*3!)\r<BR>\n" );
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document.write( "11 C 8 = (11*10*9*8!)/(8!*3!)\r<BR>\n" );
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document.write( "11 C 8 = (11*10*9)/(3!)\r<BR>\n" );
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document.write( "11 C 8 = (11*10*9)/(3*2*1)\r<BR>\n" );
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document.write( "11 C 8 = 990/6\r<BR>\n" );
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document.write( "11 C 8 = 165\r<BR>\n" );
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document.write( "Using that combination value, we can say\r<BR>\n" );
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document.write( "P(X = k) = (n C k)*(p)^(k)*(1-p)^(n-k)\r<BR>\n" );
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document.write( "P(X = 8) = (11 C 8)*(0.9)^(8)*(1-0.9)^(11-8)\r<BR>\n" );
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document.write( "P(X = 8) = (11 C 8)*(0.9)^(8)*(0.1)^(3)\r<BR>\n" );
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document.write( "P(X = 8) = (165)*(0.9)^(8)*(0.1)^3\r<BR>\n" );
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document.write( "P(X = 8) = (165)*(0.43046721)*(0.001)\r<BR>\n" );
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document.write( "P(X = 8) = 0.07102708965\r<BR>\n" );
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document.write( "P(X = 8) = 0.07\r<BR>\n" );
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document.write( "P(X = 8) = <font color=red size=4>7%</font> (move the decimal 2 spots to the right to go from 0.07 to 7%)\r<BR>\n" );
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document.write( "This means that the answer is <font color=red size=4>Choice B</font></font> </SPAN>\n" );
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