document.write( "Question 1199988: In a sequence of independent rolls of a fair die, find the probability that
\n" ); document.write( "i) The first 3 is observed on the fifth trial
\n" ); document.write( "ii) At least 4 trials are required to obtain a 1
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Algebra.Com's Answer #833982 by ikleyn(52915) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "In a sequence of independent rolls of a fair die, find the probability that
\n" ); document.write( "i) The first \"3\" is observed on the fifth trial
\n" ); document.write( "ii) At least 4 trials are required to obtain a \"1\"
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\n" ); document.write( "\n" ); document.write( " In this my post, I will solve part (i), ONLY.\r
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document.write( "Event in part (i) is the intersection of two independent events E and F.\r\n" );
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document.write( "    Event E is that first 4 rolls are \"not 3\".\r\n" );
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document.write( "    Event F is that the 5-th draw is \"3\".\r\n" );
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document.write( "Therefore, the probability of event in part (i) is\r\n" );
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document.write( "    P(event in part (i) ) =  = .    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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