document.write( "Question 617935: Suppose we want to determine the (binomial) probability(p) of getting 5 heads in 11 flips of a 2-sided coin. Using the Binomial Probabilities Table in Appendix B of the text, what values of n, x and p would we use to look up this probability, and what would be the probability?
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Algebra.Com's Answer #388645 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
the value of n would be 11
\n" ); document.write( "the value of x would be 5
\n" ); document.write( "the value of p would be .5
\n" ); document.write( "the value of q = 1-p would also be .5
\n" ); document.write( "the formula is:
\n" ); document.write( "nCx*p^x*q^(n-x)
\n" ); document.write( "you should get:
\n" ); document.write( "11C5*.5^5*.5^6 equals .225585938
\n" ); document.write( "11C5 is equivalent to 11! / (5!*6!) which is equal to 462
\n" ); document.write( ".5^5 is equal to .03125
\n" ); document.write( ".5^6 is equal to .015625
\n" ); document.write( "all of the probabilities are shown in the following table.
\n" ); document.write( "the sum of the probabilities should be equal to 1 as shown.
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document.write( "n	x	nCx	(.5)^x	        (.5)^(n-x)	nCx*(.5)^x*(.5)^(n-x)\r\n" );
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document.write( "11	0	1	1	        0.000488281	0.000488281\r\n" );
document.write( "11	1	11	0.5	        0.000976563	0.005371094\r\n" );
document.write( "11	2	55	0.25	        0.001953125	0.026855469\r\n" );
document.write( "11	3	165	0.125	        0.00390625	0.080566406\r\n" );
document.write( "11	4	330	0.0625	        0.0078125	0.161132813\r\n" );
document.write( "11	5	462	0.03125	        0.015625	0.225585938 *****\r\n" );
document.write( "11	6	462	0.015625	0.03125	        0.225585938\r\n" );
document.write( "11	7	330	0.0078125	0.0625	        0.161132813\r\n" );
document.write( "11	8	165	0.00390625	0.125	        0.080566406\r\n" );
document.write( "11	9	55	0.001953125	0.25	        0.026855469\r\n" );
document.write( "11	10	11	0.000976563	0.5	        0.005371094\r\n" );
document.write( "11	11	1	0.000488281	1	        0.000488281\r\n" );
document.write( "				total probability >>>>>	1\r\n" );
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