# Question

Refer to Exercise 5.70.

a. Estimate the median percentage of SiO2 using a 95% confidence interval.

b. Evaluate whether the median percentage of SiO2 is different from 6.2% using an a = .05 test of hypotheses.

a. Estimate the median percentage of SiO2 using a 95% confidence interval.

b. Evaluate whether the median percentage of SiO2 is different from 6.2% using an a = .05 test of hypotheses.

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