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Solution 3 of 4 B8 Tables A hospital director is told that 55 % of the emergency room visitors are insured. The director wants to test the claim that the percentage of insured patients is below the expected percentage. A sample of 320 patients found that 160 were insured. Make the decision to reject or fail to reject the null hypothesis at the 0.01 level. Now that we have the test statistic, we can calculate the P-value. The P-value is the probability of observing a value of the test statistic as extreme or more extreme than the one observed in the data, assuming the null hypothesis is true. In this situtation, that means that the value we want to find is P(z £ — 1.80). Using either the standard normal tables or technology, we can find this value as follows. 0.035900 —1.80 0 P(z < —1.80) = 0.0359 Thus the P-value of the test statistic is 0.0359. Continued on the next page ...