document.write( "Question 1199959: A coin is Twice as likely to turn up Head as Tails in a sequences of independent
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Algebra.Com's Answer #833958 by ikleyn(52781)\"\" \"About 
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document.write( "From the problem,  P(Head) = 2/3;  P(Tail) = 1/3.\r\n" );
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document.write( "Next, the event that the 3rd Head occurs on the 6th toss is the intersection of two independent events, A and B.\r\n" );
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document.write( "    Event A is that in the first 5 tosses the Head will occur exactly two times.\r\n" );
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document.write( "    Event B is that the 6th toss will be Head.\r\n" );
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document.write( "Event A is the binomial with the number of trials n= 5, number of success trials k= 2\r\n" );
document.write( "and the probability of success (=Head) of 2/3;  so\r\n" );
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document.write( "    P(A) = \"C%5B5%5D%5E2%2A%282%2F3%29%5E2%2A%281-2%2F3%29%5E3\" = \"10%2A%282%2F3%29%5E2%2A%281%2F3%29%5E3\" = 0.164609.\r\n" );
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document.write( "For event B,  P(B) = P(Head) = 2/3.\r\n" );
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document.write( "Therefore,  P(A and B) = P(A)*P(B) = \"0.164609%2A%282%2F3%29\" = 0.109739  (rounded).    ANSWER\r\n" );
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