Question 1064321
(B) This portion of the problem deals with the sampling distribution of the mean
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our sample size is 30, n = 30 
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we know the following information
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the sample mean is equal to the population mean
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the sample standard deviation is call the standard error(SE) and
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SE = population standard deviation / square root(n)
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SE = 1.8 / square root(30) = 0.3286
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because the sample size > or = 30, we can use the normal distribution for the sample
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z-score (X < 63 ) = ( 63 - 62.4 ) / 0.3286 = 1.8259
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Probability ( X < 63 ) = 0.9664
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