A random sample of 200 printed circuit boards contains 18 defective or nonconforming units. Estimate the process fraction nonconforming.
(a) Test the hypothesis that the true fraction nonconforming in this process is 0.10. Use a = 0.05. Find the P-value.
(b) Construct a 90% two-sided confidence interval on the true fraction nonconforming in the production process.