Bill, a psychologist, has developed a new aptitude test. He was able to show that 80% of the public passed the test. A second psychologist, Tamera, wants to recreate this study. She believes the actual percentage is less than 80%. A random sample of 200 people took the test, and 146 passed. Does Tamera have enough evidence to say that Bill's test is invalid? Use alpha = 0.01. (12 points)
State the null and alternative hypotheses:
Give the point estimate for the proportion of people who passed the test:
Calculate the test statistic:
Determine the p-value:
Decision: