document.write( "Question 862894: Suppose a coin is flipped 15 times. Let X = the number of tails that are observed.
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Algebra.Com's Answer #520118 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "That's the same as the mean of a binomial event with\r\n" );
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document.write( "n=15, p=\r\n" );
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document.write( "E(X) = mean(X) = np =  = \r\n" );
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document.write( "[Even though you would never really EXPECT to ever get  tails,\r\n" );
document.write( "that's about what you would expect to AVERAGE getting, if, say, you\r\n" );
document.write( "flipped the coin 15 times every day for several years, and kept a running\r\n" );
document.write( "average of how many tails you got daily.]\r\n" );
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document.write( "Edwin

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