Standard deviation

Calculate the standard deviation between two means assuming that the sample obtained from normally distributed populations having equal variances.

H0: ?A ? ?B, and H1: ?A > ?B X ? 1 = 12, X ? 2 = 9, s1= 5, s2 = 3, n1 =15, n2 =14.

(x1-x2)/SQRT[2 MSE/(2) (1/N1 + 1/N2]

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