Question 187049
In testing the hypothesis, 
Ho: µ &#8805; 28.7 and Ha: µ < 28.7, using the p-value approach, a p-value of 0.0764 was obtained. 
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Draw the picture with a left tail having area = 0.0764
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The corresponding z-value is z = -1.4297
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If (standard deviation symbol)= 9.8, find the sample mean which produced this p-value given that the sample of size n = 40 was randomly selected. 
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Use the formula z = (x-u)/s
-1.4297 = (28.7-u)/9.8
28.7-u = -14.0112
u = 14.69
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Cheers,
Stan H.