Question 1071281
The standard error(SE) of the mean is 16 / square root(64) = 2
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alpha(a) = 1 - (95/100) = 0.05
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The critical probability (p*): p* = 1 - a/2 = 1 - 0.05/2 = 0.975
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Use z-table(sample > 40) to find crical value(CV) associated with p*
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CV = 1.96
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margin of error(ME) = CV * SE = 1.96 * 2 = 3.92
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95% confidence interval(CI) = sample statistic + or - ME
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95% CI = 119 + or - 3.92 = (115.08, 122.92)
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