To combat antibiotic resistance, the Quality Improvement Consortium recommends a throat swab to con firm strep throat before a physician prescribes antibiotics to children under age 5. In a random sample of 60 children who received antibiotics for throat infections, 18 did not have a throat swab.
(a) At α = .05, is this a statistically significant reduction over last year's national rate of 40 percent?
(b) Is it safe to assume normality of the sample proportion p? Explain.