<PRE><B>Question 1051028</B>
Because H_a contains not equal, we use a two-tailed test
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The test is for population mean and we can use the Normal distribution since
we are given that the population is normally distributed and the sample size is &gt; 30
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we use the standard error of the mean to calculate the test statistic
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sample size is 225, the square root of 225 = 15, then
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standard error of the mean = 30 / 15 = 2
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test statistic is z = (745 - 750) / 2 = -2.500
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significance level is 0.1005 and we use the absolute value of the z-score
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The p-value associated with 2.500 is 1 - 0.9938 = 0.0062
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Since this is a two-tailed test we multiply by 2 = 0.0124 2-tailed p-value
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Since 0.0125 is less than 0.1005, we reject H_0
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