document.write( "Question 1118388: The mean salary offered to students who are graduating from Coastal State University this year is $24,215, with a standard deviation of $3678. A random sample of 85 Coastal State students graduating this year has been selected. What is the probability that the mean salary offer for these 85 students is $24,500 or less? \n" ); document.write( "
Algebra.Com's Answer #733733 by Theo(13342)\"\" \"About 
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the population mean is 24215
\n" ); document.write( "the population standard deviation is 3678.\r
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\n" ); document.write( "\n" ); document.write( "the sample size is 85.
\n" ); document.write( "the standard deviation of the distribution of sample means, called the standard error, from samples whose size is 85 is equal to 3678 / sqrt(85) = 398.9351119.\r
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\n" ); document.write( "\n" ); document.write( "the z-score for a sample mean of 24500 or less from this population, with a sample size of 85, is z = (24500 - 24215) / 398.9351119 = .7143732313.\r
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\n" ); document.write( "\n" ); document.write( "the area under the normal distribution curve to the left of this z-score is equal to .7625107243.\r
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\n" ); document.write( "\n" ); document.write( "that means the probability that you would get a sample of size 85 whose mean is 24500 or less is .7625107243, or approximately 76.25%.\r
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\n" ); document.write( "\n" ); document.write( "this can be seen visually in the following graph.\r
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