1. To assess the accuracy of a kitchen scale a standard weight known to weigh 1 gram is weighed a total of n times and the mean,x' , of the weighings is computed. Suppose the scale readings are Normally distributed with unknown mean, µ, and standard deviation σ = 0.01 g. How large should n be so that a 90% confidence interval for µ has a margin of error of ± 0.0001?
A. 165
B. 27061
C. 38416
2. What is the P-value for a test of the hypotheses H0: μ = 10 against Ha: μ ≠ 10 if the calculated statistic is z = 2.56?
A. 0.0052
B. 0.0104
C. 0.9948
3. I have computed a 95% confidence interval for the mean, μ, of a population as (13, 20). Based on this interval, we can say
A. a null hypothesis that μ = 14 is not rejected at α = 5%.
B. a null hypothesis that μ = 24 is rejected at α = 5%.
C. Both choices are correct.