document.write( "Question 1184149: Consider a random variable Y = 2X + 7, where X is a random variable with mean 3 and standard deviation 2.\r
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Algebra.Com's Answer #814691 by Edwin McCravy(20056)\"\" \"About 
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document.write( "If X is a random variable with mean μ and standard deviation σ,\r\n" );
document.write( "then the random variable Y = aX + b has mean = aμ + b, and \r\n" );
document.write( "standard deviation aσ.\r\n" );
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document.write( "Therefore, since X is a random variable with mean 3 and standard deviation 2,\r\n" );
document.write( "random variable Y = 2X + 7 has mean 2(3) + 7 = 13 and standard deviation \r\n" );
document.write( "2(2) = 4, so its variance is 42 = 16.\r\n" );
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document.write( "Edwin
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