document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1097576>Question 1097576</A>: <I><SPAN STYLE=\"word-break: break-all;\"> HELPPPPPPPPPP MEEEEEE \r<BR>\n" );
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document.write( "Suppose we want to determine the (binomial) probability (p) of getting 2 heads in 5 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 #712049 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=712049\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> you want to find the binomial probability of getting 2 heads out of 5 flips.\r<BR>\n" );
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document.write( "the formula for p(x) = c(n,x) * p^x * q^(n-x)\r<BR>\n" );
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document.write( "c(n,x) is the number of ways you can get sets of x out of sets of n where order within the set is not required.\r<BR>\n" );
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document.write( "p is the probability of occurrence.<BR>\n" );
document.write( "q is the 1 minus the probability of occurence.<BR>\n" );
document.write( "x is the number of successes you want out of n tries.<BR>\n" );
document.write( "n is the total number of possible tries.\r<BR>\n" );
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document.write( "in your problem, you would have.\r<BR>\n" );
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document.write( "c(n,x) = c(5,2) which is the possible number of sets of 2 elements you can get out of a set of 5 elements where order is not important.<BR>\n" );
document.write( "p = .5 because the probability of getting a head on a single flip of the coin is .5.<BR>\n" );
document.write( "q = 1 minus .5 = .5 which is the probability of NOT getting a head on a single flip of the coin.<BR>\n" );
document.write( "x is equal to 2 which is the  number of times out of 5 that you want to flip a head.<BR>\n" );
document.write( "n is equal to 5 which is the total number of times you are flipping the coin.\r<BR>\n" );
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document.write( "in your problem, the general equation of p(x) = c(n,x) * p^x * q^(n-x) becomes:\r<BR>\n" );
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document.write( "p(2) = c(5,2) * .5^2 * .5^3\r<BR>\n" );
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document.write( "work this out and you get p(2) = .3125\r<BR>\n" );
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document.write( "to find this in the table, you would look for the table that has n = 5 and you would look for the row that has 2 in it and then you would look for the column that has .5 in it.\r<BR>\n" );
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document.write( "the answer shown in the table that i used is the same at .3125.\r<BR>\n" );
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document.write( "this is the best and most complete table i could find on the web.\r<BR>\n" );
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document.write( "hopefully your table is constructed in a similar mnner.\r<BR>\n" );
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document.write( "this table is good because it has multiple tables with  n = 1 to n = 29.\r<BR>\n" );
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document.write( "it can be found here:\r<BR>\n" );
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document.write( "<a  rel=nofollow HREF= \"http://www.pindling.org/Math/Statistics/Textbook/Functions/Binomial/binomial_2_8.htm\" target = \"_blank\">http://www.pindling.org/Math/Statistics/Textbook/Functions/Binomial/binomial_2_8.htm</a>\r<BR>\n" );
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document.write( "here's a picture of the table that i used with the correct selection made.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src= \"http://theo.x10hosting.com/2017/101501.jpg\" alt=\"$$$\" >\r<BR>\n" );
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document.write( "the particular page i selected was on the top row which said n = 2 to 8.\r<BR>\n" );
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document.write( "i then found the table with n = 5 and looked for the row with x = 2 and then found the corresponding column with p = .5.\r<BR>\n" );
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document.write( "the intersection of the row with x = 2 on it and the column with p = .5 on it gave me the result of .3125.\r<BR>\n" );
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document.write( "this is exactly what i manually calculated.\r<BR>\n" );
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document.write( "there are also calculators on the web you can use to get the binomial probability.\r<BR>\n" );
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document.write( "one such calculator can be found here.\r<BR>\n" );
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document.write( "<a  rel=nofollow HREF= \"http://stattrek.com/online-calculator/binomial.aspx\" target = \"_blank\">http://stattrek.com/online-calculator/binomial.aspx</a>\r<BR>\n" );
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document.write( "for your problem, you would give it probability of success on a single trial is .5 and number of trials is 5 and number of successes is 2.\r<BR>\n" );
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document.write( "it will tell you that the probabilility of getting 2 successes out of 5 trials is .3125, same as the table.\r<BR>\n" );
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document.write( "it also tells you all sorts of other things about the probability of 2 out of 5 that you might want to know, such as the probabilility of getting less than 2 successes, less than or equal, more than, etc.\r<BR>\n" );
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document.write( "this is a great calculator to use to check your work, but don't cheat, since the calculator will more then likely not be at your disposal when you take a test in class.\r<BR>\n" );
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document.write( "for your infomation, the frmula of c(n,x) is:\r<BR>\n" );
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document.write( "c(n,x) = n! / (x! * (n-x)!)\r<BR>\n" );
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document.write( "c(5,2) would be equal to 5! / (2! * 3!) which would be equal to:\r<BR>\n" );
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document.write( "              5 * 4 * 3 * 2 * 1\r\n" );
document.write( "        ----------------------------\r\n" );
document.write( "              2 * 1 * 3 * 2 * 1\r\n" );
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document.write( "</PRE>\r<BR>\n" );
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document.write( "you wind up with c(5,2) = 10\r<BR>\n" );
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document.write( " </SPAN>\n" );
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