document.write( "Question 825048: The standard deviation of a binomial distribution for which n = 100 and p = 0.40 is 24.0.\r
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Algebra.Com's Answer #496969 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The formula for the standard deviation of a binomial distribution is\r\n" );
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document.write( "s = √npq\r\n" );
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document.write( "where q = 1-p = 1-0.40 = 0.60\r\n" );
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document.write( "or you may have learned the formula without q, but with 1-p like this:\r\n" );
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document.write( "s = √np(1-p)\r\n" );
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document.write( "s = √100(0.40)(0.60)\r\n" );
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document.write( "s = √24 = 4.8990\r\n" );
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document.write( "So it's the square root of 24, (not 24 without a square root over it.)\r\n" );
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document.write( "Answer: false\r\n" );
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document.write( "Note: the formula for the mean is m = np without a square root.\r\n" );
document.write( "But the formula for the standard deviation does have a square root.\r\n" );
document.write( "If you had been asked for the variance s² = npq, not the standard \r\n" );
document.write( "deviation, then 24 would have been the answer, but the standard \r\n" );
document.write( "deviation is the square root of the variance.\r\n" );
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document.write( "Edwin
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