document.write( "Question 1124876: A fair coin is tossed nine times, with the result (H or T) of each flip noted. \r
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\n" ); document.write( "\n" ); document.write( "How many outcomes does the experiment have? \r
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\n" ); document.write( "\n" ); document.write( "How many outcomes are there where heads comes up three times? \r
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\n" ); document.write( "\n" ); document.write( "What is the probability of the outcome HHHTTTTTT?
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\n" ); document.write( "\n" ); document.write( "What is the probability that heads comes up three times?
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Algebra.Com's Answer #741166 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
2^9 = 512 outcomes
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\n" ); document.write( "the binomial probability formula is
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\n" ); document.write( "Probability (P) ( k successes in n trials ) = nCk * p^k * (1-p)^(n-k), where nCk = n!/k!(n-k)!, p is probability of success
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\n" ); document.write( "if k = 3, then
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\n" ); document.write( "P (3 heads in 9 trials) = 9C3 * (1/2)^3 * (1-(1/2))^(9-3) =
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\n" ); document.write( "9!/3!(9-3)! * (1/8) * (1/64) =
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\n" ); document.write( "(9*8*7/(3*2)) * (1/512) =
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\n" ); document.write( "84/512
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\n" ); document.write( "There are 84 outcomes where heads comes up three times
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\n" ); document.write( "P of HHHTTTTTT = (1/2)^3 * (1/2)^6 = (1/8) * (1/64) = 1/512
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\n" ); document.write( "P heads comes up three times is 84/512 = 21/128
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