document.write( "Question 477789: the average teachers salary in NJ (ranked first among states) is $52,174. Suppose that the distribution is normal with standard deviation equal to $7500.\r
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\n" ); document.write( "\n" ); document.write( "b/ If we sample 100 teachers salaries, what is the probability that the sample mean is less than $50,000 \n" ); document.write( "

Algebra.Com's Answer #327406 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "μ =  $52,174 
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document.write( "σ =  $7500
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document.write( "a) z = (50,000-52,174)/7500 = -.2899  NORMSDIST(-0.2899) = .386 OR 38.6%
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document.write( "b) z = -2174/[7500/sqrt(100)]  = -2.8987  NORMSDIST(2.8987)= .0019 OR .19 % \n" );
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