A statistician has framed his hypothesis testing problem as:
Ho: mean = 100 H1: mean < 100
Specify the region for the p-statistic which will lead to the rejection of the null at the 80% significance level.
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A. B. C. D.Explanation
Since the alternative is directional and to the left, we use a left-tailed test. For this, the critical value at 80% level is -0.84. -0.84 is the value above which 80% of the probability mass of the standard normal distribution lies). The rejection region is then given by z-statistic < -0.84.