Question 477663
The College Board reports that the nationwide mean SAT Math score was 515 in 2007. Assume that SAT scores are normally distributed with a standard deviation of 116. 
A.) What is the probability that a randomly selected student got an SAT score less than 500.
z(500) = (500-515)/116 = -0.1293
P(x < 500) = P(z < -0.1293) = 0.4486
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B.) Suppose you choose samples of SAT Math scores of size 16. Find the random sample mean and the random sample standard deviation. 
C.) What is the probability that a sample of 16 students will have a sample mean SAT Math score below 500?
z(500) = (500-515)/(116/sqrt(15)) = -0.5172
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P(x-bar < 500) = P(z < -0.5172) = 0.3025
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Cheers,
Stan H.
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