Repeat Example 9.8 by constructing a confidence interval for p. = 606.40 versus Ax: & # 606.40 at the 3% Snince level Weusen 30.4 - 622.35, and o - 65, aong with a = 0.05, 10 determine a 95% confidence interval, We find zu/2 = Zous = 1.96 and compute = 622.85=1.96 65 = 622.85 = 23.26. V30 resulting in the interval [599.59, 646.111. Since the hypothesized value of the population mean Mo = 606.40 falls within the 95% confidence interval, we do not reject Ho. Thus, we arrive at the same conclusion as with the p-value and the critical value approaches; that is, the sample data do not support the research analyst's claim that average back-to-school spending differs from $606,40 per family this year