document.write( "Question 253224: a fair coin is tossed 3 times,
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Algebra.Com's Answer #185495 by Edwin McCravy(20056) $\"\"$ $\"About$

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a fair coin is tossed 3 times,
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document.write( "Space      2 heads (exactly)?   3 heads?  More heads than tails?  \r\n" );
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document.write( "HHH               NO               YES              YES\r\n" );
document.write( "HHT              YES                NO              YES\r\n" );
document.write( "HTH              YES                NO              YES\r\n" );
document.write( "HTT               NO                NO               NO\r\n" );
document.write( "THH              YES                NO              YES \r\n" );
document.write( "THT               NO                NO               NO\r\n" );
document.write( "TTH               NO                NO               NO\r\n" );
document.write( "TTT               NO                NO               NO \r\n" );
document.write( "result        3 out of 8        1 out of 8       4 out of 8\r\n" );
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document.write( "P(2 heads) = 3/8\r\n" );
document.write( "P(3 heads) = 1/8\r\n" );
document.write( "P(more heads than tails) = 4/8 = 1/2               \r\n" );
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document.write( "Also you can do this using binomial formulas:\r\n" );
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document.write( "P(2 heads) = \r\n" );
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document.write( "P(3 heads) = \r\n" );
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document.write( "P(more heads than tails) = P(2 heads OR 3 heads) = P(2 heads) + P(3 heads) = .375 + .125 = .5\r\n" );
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document.write( "Edwin

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